21807162864 has 120 divisors (see below), whose sum is σ = 61944285312. Its totient is φ = 7160832000.

The previous prime is 21807162863. The next prime is 21807162899. The reversal of 21807162864 is 46826170812.

21807162864 is a `hidden beast` number, since 2 + 18 + 0 + 7 + 1 + 628 + 6 + 4 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21807162863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3111364 + ... + 3118364.

Almost surely, 2^21807162864 is an apocalyptic number.

21807162864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21807162864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30972142656).

21807162864 is an abundant number, since it is smaller than the sum of its proper divisors (40137122448).

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

21807162864 is a wasteful number, since it uses less digits than its factorization.

21807162864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7335 (or 7326 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The spelling of 21807162864 in words is "twenty-one billion, eight hundred seven million, one hundred sixty-two thousand, eight hundred sixty-four".