121312631 has 4 divisors (see below), whose sum is σ = 132341064. Its totient is φ = 110284200.

The previous prime is 121312627. The next prime is 121312643. The reversal of 121312631 is 136213121.

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 121312631 - 2² = 121312627 is a prime.

It is a super-2 number, since 2×121312631² = 29433508880284322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121312691) 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, 5514200 + ... + 5514221.

It is an arithmetic number, because the mean of its divisors is an integer number (33085266).

Almost surely, 2^121312631 is an apocalyptic number.

121312631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121312631 is a deficient number, since it is larger than the sum of its proper divisors (11028433).

121312631 is a wasteful number, since it uses less digits than its factorization.

121312631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11028432.

The product of its digits is 216, while the sum is 20.

The square root of 121312631 is about 11014.2013328248. The cubic root of 121312631 is about 495.0343560142.

Adding to 121312631 its reverse (136213121), we get a palindrome (257525752).

The spelling of 121312631 in words is "one hundred twenty-one million, three hundred twelve thousand, six hundred thirty-one".