खाता संख्या सत्यापित कीजिए।

A word-by-word breakdown is:

• खाता = account
• संख्या = number
• सत्यापित = verified / verify
• कीजिए = please do

So the structure is basically:

खाता संख्या + सत्यापित कीजिए
= account number + please verify

In other words, खाता संख्या is the thing being acted on, and सत्यापित कीजिए is the polite instruction.

Because Hindi normally puts the main verb at the end of the clause.

English usually prefers Subject–Verb–Object:

• Please verify the account number.

Hindi usually prefers Subject–Object–Verb:

• खाता संख्या सत्यापित कीजिए।

Here the subject you is not stated, because commands often leave it out. So the sentence is literally closer to:

• Account number verify please-do.

That end-position for the verb is completely normal in Hindi.

कीजिए is a polite imperative form of करना (to do).

It is used to make respectful requests or instructions, similar to:

• please do
• please ...
• a polite command

So सत्यापित कीजिए literally means do verify or please verify.

Compare:

• करो = do! (informal)
• कीजिए = please do / do, respectfully
• करिए = another polite form, also common

In formal notices, forms, banking messages, and customer-service language, कीजिए sounds natural and appropriately polite.

It is functioning as the verbal element, but the fully inflected finite verb is actually कीजिए.

A useful way to think about it is:

• सत्यापित करना = to verify

So in the imperative:

• सत्यापित कीजिए = please verify

This is a very common Hindi pattern, especially with formal or Sanskrit-derived vocabulary:

• जाँच कीजिए = please check
• पुष्टि कीजिए = please confirm
• सत्यापित कीजिए = please verify

So सत्यापित carries the core meaning, while कीजिए supplies the polite command form.

Both can mean number, but they differ in style.

• संख्या is more formal, official, and Sanskrit-based.
• नंबर is more everyday and conversational.

So:

• खाता संख्या sounds formal, official, bureaucratic, or technical.
• खाता नंबर sounds more everyday and spoken.

On a banking form, website, app, or official notice, संख्या is very natural. In casual speech, many people would say खाता नंबर.

Because Hindi does not always mark direct objects with को.

In this sentence, खाता संख्या is an inanimate direct object, and in this type of instruction it is very normal to leave it unmarked:

• खाता संख्या सत्यापित कीजिए।

Using को here would sound less natural in this formal instruction style.

A rough rule for learners is:

• को is often used with animate/specific objects
• but many inanimate direct objects appear without को

So the lack of को here is normal Hindi grammar.

Yes. It is a compact noun phrase meaning account number.

Hindi often puts one noun before another to specify it, especially in formal expressions:

• खाता संख्या = account number
• फोन संख्या would sound formal for phone number
• आवेदन पत्र = application form
• जन्म तिथि = date of birth

In everyday spoken Hindi, people may instead use a more conversational structure or an English borrowing, but formal written Hindi often prefers these compact noun compounds.

A useful learner-friendly pronunciation is:

khā-tā saṅ-khyā sat-yā-pit kī-ji-ye

A slightly smoother approximation:

• खाता = khaa-taa
• संख्या = sunkh-yaa or sankh-yaa
• सत्यापित = sut-yaa-pit / sat-yaa-pit
• कीजिए = kee-jee-ye

A more natural rhythm is:

khā-tā saṅkhyā satyāpit kījiye

Two pronunciation notes:

• ख is an aspirated k sound, like k with a puff of air.
• ज्ञ / त्र / त्य-type clusters can feel difficult at first; in सत्यापित, the त्य part is roughly tya.

Not in this sentence.

संख्या is feminine, but सत्यापित कीजिए does not change here to match it. The polite imperative is built around कीजिए, and सत्यापित stays the same.

So you do not need to change the sentence because संख्या is feminine.

This is useful for learners, because not every Hindi predicate visibly changes for gender in every structure.

This sentence is fairly formal and very typical of:

• banking
• government forms
• websites and apps
• customer-service instructions

Common alternatives include:

• खाता संख्या जाँचिए। = Check the account number.
• खाता संख्या की पुष्टि कीजिए। = Please confirm the account number.
• खाता नंबर सत्यापित कीजिए। = Same meaning, but with the more everyday नंबर
• कृपया खाता संख्या सत्यापित करें। = Please verify the account number.
  This is also very common in formal written Hindi.

So the original sentence sounds polished, official, and polite.