12999631 has 4 divisors (see below), whose sum is σ = 13301992. Its totient is φ = 12697272.

The previous prime is 12999587. The next prime is 12999641. The reversal of 12999631 is 13699921.

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 12999631 - 2¹³ = 12991439 is a prime.

It is a super-2 number, since 2×12999631² = 337980812272322, which contains 22 as substring.

It is the 3606-th Hogben number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12999641) by changing a digit.

It is a nontrivial repunit in base 3605.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151116 + ... + 151201.

It is an arithmetic number, because the mean of its divisors is an integer number (3325498).

Almost surely, 2^12999631 is an apocalyptic number.

12999631 is a deficient number, since it is larger than the sum of its proper divisors (302361).

12999631 is an equidigital number, since it uses as much as digits as its factorization.

12999631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302360.

The product of its digits is 26244, while the sum is 40.

The square root of 12999631 is about 3605.5001040078. The cubic root of 12999631 is about 235.1312440267.

The spelling of 12999631 in words is "twelve million, nine hundred ninety-nine thousand, six hundred thirty-one".