129312931 has 16 divisors (see below), whose sum is σ = 150927840. Its totient is φ = 109486080.

The previous prime is 129312907. The next prime is 129312947. The reversal of 129312931 is 139213921.

It is not a de Polignac number, because 129312931 - 2¹⁵ = 129280163 is a prime.

It is a super-2 number, since 2×129312931² = 33443668247621522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129312893 and 129312902.

It is not an unprimeable number, because it can be changed into a prime (129312961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14575 + ... + 21703.

It is an arithmetic number, because the mean of its divisors is an integer number (9432990).

Almost surely, 2^129312931 is an apocalyptic number.

129312931 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

129312931 is a deficient number, since it is larger than the sum of its proper divisors (21614909).

129312931 is a wasteful number, since it uses less digits than its factorization.

129312931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7254.

The product of its digits is 2916, while the sum is 31.

The square root of 129312931 is about 11371.5843663053. The cubic root of 129312931 is about 505.6856757814.

The spelling of 129312931 in words is "one hundred twenty-nine million, three hundred twelve thousand, nine hundred thirty-one".