21731457152 has 16 divisors (see below), whose sum is σ = 43293137550. Its totient is φ = 10865728512.

The previous prime is 21731457127. The next prime is 21731457173. The reversal of 21731457152 is 25175413712.

It can be written as a sum of positive squares in only one way, i.e., 14317558336 + 7413898816 = 119656^2 + 86104^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×21731457152² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84888377 + ... + 84888632.

Almost surely, 2^21731457152 is an apocalyptic number.

It is an amenable number.

21731457152 is a deficient number, since it is larger than the sum of its proper divisors (21561680398).

21731457152 is an equidigital number, since it uses as much as digits as its factorization.

21731457152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169777023 (or 169777011 counting only the distinct ones).

The product of its digits is 58800, while the sum is 38.

The spelling of 21731457152 in words is "twenty-one billion, seven hundred thirty-one million, four hundred fifty-seven thousand, one hundred fifty-two".