21878413860 has 48 divisors (see below), whose sum is σ = 61613689536. Its totient is φ = 5800516992.

The previous prime is 21878413841. The next prime is 21878413913. The reversal of 21878413860 is 6831487812.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1043494 + ... + 1064253.

It is an arithmetic number, because the mean of its divisors is an integer number (1283618532).

Almost surely, 2^21878413860 is an apocalyptic number.

21878413860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21878413860 is an abundant number, since it is smaller than the sum of its proper divisors (39735275676).

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

21878413860 is a wasteful number, since it uses less digits than its factorization.

21878413860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2107932 (or 2107930 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 48.

The spelling of 21878413860 in words is "twenty-one billion, eight hundred seventy-eight million, four hundred thirteen thousand, eight hundred sixty".