11815631 has 4 divisors (see below), whose sum is σ = 11958072. Its totient is φ = 11673192.

The previous prime is 11815627. The next prime is 11815633. The reversal of 11815631 is 13651811.

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 11815631 - 2² = 11815627 is a prime.

It is a super-2 number, since 2×11815631² = 279218271856322, 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 11815631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11815633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71096 + ... + 71261.

It is an arithmetic number, because the mean of its divisors is an integer number (2989518).

Almost surely, 2^11815631 is an apocalyptic number.

11815631 is a deficient number, since it is larger than the sum of its proper divisors (142441).

11815631 is an equidigital number, since it uses as much as digits as its factorization.

11815631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142440.

The product of its digits is 720, while the sum is 26.

The square root of 11815631 is about 3437.3872345140. The cubic root of 11815631 is about 227.7642929334.

The spelling of 11815631 in words is "eleven million, eight hundred fifteen thousand, six hundred thirty-one".