21437563831026 has 48 divisors (see below), whose sum is σ = 49885847630784. Its totient is φ = 6123704309856.

The previous prime is 21437563830983. The next prime is 21437563831039. The reversal of 21437563831026 is 62013836573412.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21437563831026.

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, 6447745 + ... + 9189588.

It is an arithmetic number, because the mean of its divisors is an integer number (1039288492308).

Almost surely, 2^{21437563831026} is an apocalyptic number.

21437563831026 is an abundant number, since it is smaller than the sum of its proper divisors (28448283799758).

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

21437563831026 is a wasteful number, since it uses less digits than its factorization.

21437563831026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15642015 (or 15642008 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 51.

The spelling of 21437563831026 in words is "twenty-one trillion, four hundred thirty-seven billion, five hundred sixty-three million, eight hundred thirty-one thousand, twenty-six".