21878015013760 has 64 divisors (see below), whose sum is σ = 52436583014400. Its totient is φ = 8728709232640.

The previous prime is 21878015013749. The next prime is 21878015013781. The reversal of 21878015013760 is 6731051087812.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

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, 43689856 + ... + 44187775.

It is an arithmetic number, because the mean of its divisors is an integer number (819321609600).

Almost surely, 2^{21878015013760} is an apocalyptic number.

21878015013760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21878015013760 is an abundant number, since it is smaller than the sum of its proper divisors (30558568000640).

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

21878015013760 is an equidigital number, since it uses as much as digits as its factorization.

21878015013760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87878039 (or 87878027 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 49.

The spelling of 21878015013760 in words is "twenty-one trillion, eight hundred seventy-eight billion, fifteen million, thirteen thousand, seven hundred sixty".