11555312131 has 64 divisors (see below), whose sum is σ = 14184201600. Its totient is φ = 9321984000.

The previous prime is 11555312129. The next prime is 11555312143. The reversal of 11555312131 is 13121355511.

It is not a de Polignac number, because 11555312131 - 2¹ = 11555312129 is a prime.

It is a super-2 number, since 2×11555312131² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11555312131.

It is not an unprimeable number, because it can be changed into a prime (11555312161) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 114408981 + ... + 114409081.

It is an arithmetic number, because the mean of its divisors is an integer number (221628150).

Almost surely, 2^11555312131 is an apocalyptic number.

11555312131 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11555312131 is a deficient number, since it is larger than the sum of its proper divisors (2628889469).

11555312131 is a wasteful number, since it uses less digits than its factorization.

11555312131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265 (or 231 counting only the distinct ones).

The product of its digits is 2250, while the sum is 28.

Adding to 11555312131 its reverse (13121355511), we get a palindrome (24676667642).

The spelling of 11555312131 in words is "eleven billion, five hundred fifty-five million, three hundred twelve thousand, one hundred thirty-one".