21632610636 has 432 divisors, whose sum is σ = 72704142784. Its totient is φ = 5279219712.

The previous prime is 21632610583. The next prime is 21632610641. The reversal of 21632610636 is 63601623612.

21632610636 is a `hidden beast` number, since 2 + 1 + 6 + 3 + 2 + 6 + 10 + 636 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21632610636.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 69113616 + ... + 69113928.

Almost surely, 2^21632610636 is an apocalyptic number.

21632610636 is a gapful number since it is divisible by the number (26) 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 21632610636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36352071392).

21632610636 is an abundant number, since it is smaller than the sum of its proper divisors (51071532148).

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

21632610636 is a wasteful number, since it uses less digits than its factorization.

21632610636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450 (or 428 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The spelling of 21632610636 in words is "twenty-one billion, six hundred thirty-two million, six hundred ten thousand, six hundred thirty-six".