21878476400 has 120 divisors (see below), whose sum is σ = 60714734544. Its totient is φ = 7487795200.

The previous prime is 21878476397. The next prime is 21878476439. The reversal of 21878476400 is 467487812.

It is a congruent number.

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, 71447 + ... + 221046.

Almost surely, 2^21878476400 is an apocalyptic number.

21878476400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21878476400 is an abundant number, since it is smaller than the sum of its proper divisors (38836258144).

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

21878476400 is a wasteful number, since it uses less digits than its factorization.

21878476400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292539 (or 292528 counting only the distinct ones).

The product of its (nonzero) digits is 602112, while the sum is 47.

The spelling of 21878476400 in words is "twenty-one billion, eight hundred seventy-eight million, four hundred seventy-six thousand, four hundred".