215717977812 has 48 divisors (see below), whose sum is σ = 511753898432. Its totient is φ = 70705025280.

The previous prime is 215717977777. The next prime is 215717977843. The reversal of 215717977812 is 218779717512.

It is a congruent number.

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, 2376168 + ... + 2465280.

Almost surely, 2^215717977812 is an apocalyptic number.

It is an amenable number.

215717977812 is an abundant number, since it is smaller than the sum of its proper divisors (296035920620).

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

215717977812 is a wasteful number, since it uses less digits than its factorization.

215717977812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92488 (or 92486 counting only the distinct ones).

The product of its digits is 3457440, while the sum is 57.

The spelling of 215717977812 in words is "two hundred fifteen billion, seven hundred seventeen million, nine hundred seventy-seven thousand, eight hundred twelve".