21749053922 has 6 divisors (see below), whose sum is σ = 32623893729. Its totient is φ = 10874422680.

The previous prime is 21749053901. The next prime is 21749053927. The reversal of 21749053922 is 22935094712.

It can be written as a sum of positive squares in 2 ways, for example, as 21480126721 + 268927201 = 146561^2 + 16399^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=104281.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21749053927) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 156422 + ... + 260702.

Almost surely, 2^21749053922 is an apocalyptic number.

21749053922 is a deficient number, since it is larger than the sum of its proper divisors (10874839807).

21749053922 is an frugal number, since it uses more digits than its factorization.

21749053922 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208564 (or 104283 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 44.

The spelling of 21749053922 in words is "twenty-one billion, seven hundred forty-nine million, fifty-three thousand, nine hundred twenty-two".