21650784900 has 72 divisors (see below), whose sum is σ = 63669924864. Its totient is φ = 5678889600.

The previous prime is 21650784871. The next prime is 21650784923. The reversal of 21650784900 is 948705612.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 573252 + ... + 609851.

It is an arithmetic number, because the mean of its divisors is an integer number (884304512).

Almost surely, 2^21650784900 is an apocalyptic number.

21650784900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21650784900 is an abundant number, since it is smaller than the sum of its proper divisors (42019139964).

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

21650784900 is a wasteful number, since it uses less digits than its factorization.

21650784900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1183181 (or 1183174 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 42.

The spelling of 21650784900 in words is "twenty-one billion, six hundred fifty million, seven hundred eighty-four thousand, nine hundred".