21526964560656 has 125 divisors (see below), whose sum is σ = 62479318013431. Its totient is φ = 7155666957024.

The previous prime is 21526964560627. The next prime is 21526964560721. The reversal of 21526964560656 is 65606546962512.

The square root of 21526964560656 is 4639716.

It is a perfect power (a square, a biquadrate), and thus also a powerful number.

21526964560656 is a `hidden beast` number, since 2 + 1 + 5 + 2 + 6 + 9 + 6 + 4 + 560 + 65 + 6 = 666.

It is a super-2 number, since 2×21526964560656² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21526964560593 and 21526964560602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 24 ways as a sum of consecutive naturals, for example, 59963689405 + ... + 59963689763.

Almost surely, 2^{21526964560656} is an apocalyptic number.

21526964560656 is the 4639716-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21526964560656

21526964560656 is an abundant number, since it is smaller than the sum of its proper divisors (40952353452775).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21526964560656 is an frugal number, since it uses more digits than its factorization.

21526964560656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1456 (or 364 counting only the distinct ones).

The product of its (nonzero) digits is 139968000, while the sum is 63.

The spelling of 21526964560656 in words is "twenty-one trillion, five hundred twenty-six billion, nine hundred sixty-four million, five hundred sixty thousand, six hundred fifty-six".