129312431 has 4 divisors (see below), whose sum is σ = 129441600. Its totient is φ = 129183264.

The previous prime is 129312427. The next prime is 129312433. The reversal of 129312431 is 134213921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 129312431 - 2² = 129312427 is a prime.

It is a super-2 number, since 2×129312431² = 33443409622259522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129312431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129312433) 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 3 ways as a sum of consecutive naturals, for example, 63071 + ... + 65088.

It is an arithmetic number, because the mean of its divisors is an integer number (32360400).

Almost surely, 2^129312431 is an apocalyptic number.

129312431 is a deficient number, since it is larger than the sum of its proper divisors (129169).

129312431 is a wasteful number, since it uses less digits than its factorization.

129312431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129168.

The product of its digits is 1296, while the sum is 26.

The square root of 129312431 is about 11371.5623816607. The cubic root of 129312431 is about 505.6850240209.

The spelling of 129312431 in words is "one hundred twenty-nine million, three hundred twelve thousand, four hundred thirty-one".