21664500048 has 60 divisors (see below), whose sum is σ = 60658010868. Its totient is φ = 7218224640.

The previous prime is 21664500043. The next prime is 21664500097. The reversal of 21664500048 is 84000546612.

21664500048 is a `hidden beast` number, since 2 + 1 + 6 + 645 + 0 + 0 + 0 + 4 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 12323664144 + 9340835904 = 111012^2 + 96648^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21664499985 and 21664500021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21664500043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 295486 + ... + 361442.

Almost surely, 2^21664500048 is an apocalyptic number.

It is an amenable number.

21664500048 is an abundant number, since it is smaller than the sum of its proper divisors (38993510820).

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

21664500048 is a wasteful number, since it uses less digits than its factorization.

21664500048 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68252 (or 68243 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 21664500048 in words is "twenty-one billion, six hundred sixty-four million, five hundred thousand, forty-eight".