21650511560 has 32 divisors (see below), whose sum is σ = 48726127800. Its totient is φ = 8657986560.

The previous prime is 21650511541. The next prime is 21650511587. The reversal of 21650511560 is 6511505612.

It can be written as a sum of positive squares in 4 ways, for example, as 14408161156 + 7242350404 = 120034^2 + 85102^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 93536 + ... + 228144.

Almost surely, 2^21650511560 is an apocalyptic number.

21650511560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21650511560 is an abundant number, since it is smaller than the sum of its proper divisors (27075616240).

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

21650511560 is a wasteful number, since it uses less digits than its factorization.

21650511560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138641 (or 138637 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 32.

The spelling of 21650511560 in words is "twenty-one billion, six hundred fifty million, five hundred eleven thousand, five hundred sixty".