21663526365252 has 36 divisors (see below), whose sum is σ = 55302764509356. Its totient is φ = 7149678667200.

The previous prime is 21663526365227. The next prime is 21663526365319. The reversal of 21663526365252 is 25256362536612.

21663526365252 is a `hidden beast` number, since 2 + 1 + 6 + 6 + 3 + 5 + 26 + 365 + 252 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 12543029724996 + 9120496640256 = 3541614^2 + 3020016^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2979029143 + ... + 2979036414.

Almost surely, 2^{21663526365252} is an apocalyptic number.

It is an amenable number.

21663526365252 is an abundant number, since it is smaller than the sum of its proper divisors (33639238144104).

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

21663526365252 is a wasteful number, since it uses less digits than its factorization.

21663526365252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5958065668 (or 5958065663 counting only the distinct ones).

The product of its digits is 23328000, while the sum is 54.

The spelling of 21663526365252 in words is "twenty-one trillion, six hundred sixty-three billion, five hundred twenty-six million, three hundred sixty-five thousand, two hundred fifty-two".