21699564685596 has 240 divisors, whose sum is σ = 64939223405056. Its totient is φ = 6189516809856.

The previous prime is 21699564685451. The next prime is 21699564685609. The reversal of 21699564685596 is 69558646599612.

21699564685596 is a `hidden beast` number, since 2 + 1 + 6 + 9 + 9 + 56 + 4 + 6 + 8 + 559 + 6 = 666.

It is a super-2 number, since 2×21699564685596² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4425770481 + ... + 4425775383.

Almost surely, 2^{21699564685596} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21699564685596, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32469611702528).

21699564685596 is an abundant number, since it is smaller than the sum of its proper divisors (43239658719460).

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

21699564685596 is a wasteful number, since it uses less digits than its factorization.

21699564685596 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7790 (or 7779 counting only the distinct ones).

The product of its digits is 7558272000, while the sum is 81.

The spelling of 21699564685596 in words is "twenty-one trillion, six hundred ninety-nine billion, five hundred sixty-four million, six hundred eighty-five thousand, five hundred ninety-six".