12131555 has 8 divisors (see below), whose sum is σ = 14593392. Its totient is φ = 9681568.

The previous prime is 12131549. The next prime is 12131563. The reversal of 12131555 is 55513121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12131555 - 2¹² = 12127459 is a prime.

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 12131555.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 524 + ... + 4953.

It is an arithmetic number, because the mean of its divisors is an integer number (1824174).

Almost surely, 2^12131555 is an apocalyptic number.

12131555 is a deficient number, since it is larger than the sum of its proper divisors (2461837).

12131555 is an equidigital number, since it uses as much as digits as its factorization.

12131555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5925.

The product of its digits is 750, while the sum is 23.

The square root of 12131555 is about 3483.0381852630. The cubic root of 12131555 is about 229.7764368282.

Adding to 12131555 its reverse (55513121), we get a palindrome (67644676).

The spelling of 12131555 in words is "twelve million, one hundred thirty-one thousand, five hundred fifty-five".