215666012931 has 32 divisors (see below), whose sum is σ = 296433561600. Its totient is φ = 139396798464.

The previous prime is 215666012899. The next prime is 215666012941. The reversal of 215666012931 is 139210666512.

It is not a de Polignac number, because 215666012931 - 2⁵ = 215666012899 is a prime.

It is a super-2 number, since 2×215666012931² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215666012941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 53261995 + ... + 53266043.

It is an arithmetic number, because the mean of its divisors is an integer number (9263548800).

Almost surely, 2^215666012931 is an apocalyptic number.

215666012931 is a deficient number, since it is larger than the sum of its proper divisors (80767548669).

215666012931 is a wasteful number, since it uses less digits than its factorization.

215666012931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7555.

The product of its (nonzero) digits is 116640, while the sum is 42.

The spelling of 215666012931 in words is "two hundred fifteen billion, six hundred sixty-six million, twelve thousand, nine hundred thirty-one".