21662645636252 has 12 divisors (see below), whose sum is σ = 38033114001960. Its totient is φ = 10796041635696.

The previous prime is 21662645636221. The next prime is 21662645636267. The reversal of 21662645636252 is 25263654626612.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 8820294227 + ... + 8820296682.

It is an arithmetic number, because the mean of its divisors is an integer number (3169426166830).

Almost surely, 2^{21662645636252} is an apocalyptic number.

It is an amenable number.

21662645636252 is a deficient number, since it is larger than the sum of its proper divisors (16370468365708).

21662645636252 is a wasteful number, since it uses less digits than its factorization.

21662645636252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17640591220 (or 17640591218 counting only the distinct ones).

The product of its digits is 37324800, while the sum is 56.

The spelling of 21662645636252 in words is "twenty-one trillion, six hundred sixty-two billion, six hundred forty-five million, six hundred thirty-six thousand, two hundred fifty-two".