21375914660 has 36 divisors (see below), whose sum is σ = 47376385308. Its totient is φ = 8100343872.

The previous prime is 21375914509. The next prime is 21375914683. The reversal of 21375914660 is 6641957312.

It can be written as a sum of positive squares in 2 ways, for example, as 13065404416 + 8310510244 = 114304^2 + 91162^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1473107 + ... + 1487546.

It is an arithmetic number, because the mean of its divisors is an integer number (1316010703).

Almost surely, 2^21375914660 is an apocalyptic number.

21375914660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21375914660 is an abundant number, since it is smaller than the sum of its proper divisors (26000470648).

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

21375914660 is a wasteful number, since it uses less digits than its factorization.

21375914660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2960700 (or 2960679 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 44.

The spelling of 21375914660 in words is "twenty-one billion, three hundred seventy-five million, nine hundred fourteen thousand, six hundred sixty".