21400202153664 has 84 divisors (see below), whose sum is σ = 61341956665600. Its totient is φ = 7133151720960.

The previous prime is 21400202153647. The next prime is 21400202153761. The reversal of 21400202153664 is 46635120200412.

21400202153664 is a `hidden beast` number, since 2 + 1 + 40 + 0 + 2 + 0 + 21 + 536 + 64 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16249362 + ... + 17516910.

Almost surely, 2^{21400202153664} is an apocalyptic number.

21400202153664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21400202153664 is an abundant number, since it is smaller than the sum of its proper divisors (39941754511936).

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

21400202153664 is a wasteful number, since it uses less digits than its factorization.

21400202153664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1296878 (or 1296865 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The spelling of 21400202153664 in words is "twenty-one trillion, four hundred billion, two hundred two million, one hundred fifty-three thousand, six hundred sixty-four".