20856167612400 has 120 divisors (see below), whose sum is σ = 68964394361344. Its totient is φ = 5382236793600.

The previous prime is 20856167612359. The next prime is 20856167612419. The reversal of 20856167612400 is 421676165802.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 20856167612400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 280287634 + ... + 280362033.

Almost surely, 2^{20856167612400} is an apocalyptic number.

20856167612400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20856167612400 is an abundant number, since it is smaller than the sum of its proper divisors (48108226748944).

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

20856167612400 is a wasteful number, since it uses less digits than its factorization.

20856167612400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560649719 (or 560649708 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 48.

The spelling of 20856167612400 in words is "twenty trillion, eight hundred fifty-six billion, one hundred sixty-seven million, six hundred twelve thousand, four hundred".