21662124400 has 60 divisors (see below), whose sum is σ = 59478012112. Its totient is φ = 7427013120.

The previous prime is 21662124391. The next prime is 21662124413. The reversal of 21662124400 is 442126612.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

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, 3865437 + ... + 3871036.

Almost surely, 2^21662124400 is an apocalyptic number.

21662124400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21662124400 is an abundant number, since it is smaller than the sum of its proper divisors (37815887712).

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

21662124400 is a wasteful number, since it uses less digits than its factorization.

21662124400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7736498 (or 7736487 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The spelling of 21662124400 in words is "twenty-one billion, six hundred sixty-two million, one hundred twenty-four thousand, four hundred".