11656724121 has 48 divisors (see below), whose sum is σ = 20135044800. Its totient is φ = 6645614976.

The previous prime is 11656724099. The next prime is 11656724159. The reversal of 11656724121 is 12142765611.

It is not a de Polignac number, because 11656724121 - 2¹⁸ = 11656461977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11656724221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 576145 + ... + 596033.

It is an arithmetic number, because the mean of its divisors is an integer number (419480100).

Almost surely, 2^11656724121 is an apocalyptic number.

It is an amenable number.

11656724121 is a deficient number, since it is larger than the sum of its proper divisors (8478320679).

11656724121 is a wasteful number, since it uses less digits than its factorization.

11656724121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20355 (or 20342 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The spelling of 11656724121 in words is "eleven billion, six hundred fifty-six million, seven hundred twenty-four thousand, one hundred twenty-one".