21637632960 has 168 divisors, whose sum is σ = 76825547136. Its totient is φ = 5583882240.

The previous prime is 21637632899. The next prime is 21637633013. The reversal of 21637632960 is 6923673612.

21637632960 is a `hidden beast` number, since 2 + 1 + 6 + 3 + 7 + 632 + 9 + 6 + 0 = 666.

It is a super-2 number, since 2×21637632960² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 31899 + ... + 210458.

Almost surely, 2^21637632960 is an apocalyptic number.

21637632960 is a gapful number since it is divisible by the number (20) 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 21637632960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38412773568).

21637632960 is an abundant number, since it is smaller than the sum of its proper divisors (55187914176).

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

21637632960 is a wasteful number, since it uses less digits than its factorization.

21637632960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242411 (or 242398 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 45.

The spelling of 21637632960 in words is "twenty-one billion, six hundred thirty-seven million, six hundred thirty-two thousand, nine hundred sixty".