31261216212 has 36 divisors (see below), whose sum is σ = 79045561140. Its totient is φ = 10417220352.

The previous prime is 31261216201. The next prime is 31261216229. The reversal of 31261216212 is 21261216213.

31261216212 is a `hidden beast` number, since 3 + 1 + 26 + 12 + 1 + 621 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 22799792016 + 8461424196 = 150996^2 + 91986^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 11787 + ... + 250322.

Almost surely, 2^31261216212 is an apocalyptic number.

It is an amenable number.

31261216212 is an abundant number, since it is smaller than the sum of its proper divisors (47784344928).

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

31261216212 is a wasteful number, since it uses less digits than its factorization.

31261216212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265432 (or 265427 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

Subtracting from 31261216212 its reverse (21261216213), we obtain a palindrome (9999999999).

The spelling of 31261216212 in words is "thirty-one billion, two hundred sixty-one million, two hundred sixteen thousand, two hundred twelve".