31912221913 has 32 divisors (see below), whose sum is σ = 39516704640. Its totient is φ = 25336488960.

The previous prime is 31912221839. The next prime is 31912221917.

31912221913 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 31912221913 - 2¹³ = 31912213721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31912221917) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2158081 + ... + 2172817.

It is an arithmetic number, because the mean of its divisors is an integer number (1234897020).

Almost surely, 2^31912221913 is an apocalyptic number.

It is an amenable number.

31912221913 is a deficient number, since it is larger than the sum of its proper divisors (7604482727).

31912221913 is a wasteful number, since it uses less digits than its factorization.

31912221913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15577.

The product of its digits is 5832, while the sum is 34.

The spelling of 31912221913 in words is "thirty-one billion, nine hundred twelve million, two hundred twenty-one thousand, nine hundred thirteen".