12155631 has 4 divisors (see below), whose sum is σ = 16207512. Its totient is φ = 8103752.

The previous prime is 12155617. The next prime is 12155641. The reversal of 12155631 is 13655121.

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 12155631 - 2⁶ = 12155567 is a prime.

It is a super-2 number, since 2×12155631² = 295518730016322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12155641) 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, 2025936 + ... + 2025941.

It is an arithmetic number, because the mean of its divisors is an integer number (4051878).

Almost surely, 2^12155631 is an apocalyptic number.

12155631 is a deficient number, since it is larger than the sum of its proper divisors (4051881).

12155631 is an equidigital number, since it uses as much as digits as its factorization.

12155631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4051880.

The product of its digits is 900, while the sum is 24.

The square root of 12155631 is about 3486.4926502145. The cubic root of 12155631 is about 229.9283393639.

The spelling of 12155631 in words is "twelve million, one hundred fifty-five thousand, six hundred thirty-one".