11656451431 has 4 divisors (see below), whose sum is σ = 11674086664. Its totient is φ = 11638816200.

The previous prime is 11656451369. The next prime is 11656451449. The reversal of 11656451431 is 13415465611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13415465611 = 65983 ⋅203317.

It is a cyclic number.

It is not a de Polignac number, because 11656451431 - 2⁹ = 11656450919 is a prime.

It is a super-2 number, since 2×11656451431² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11656451231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8816625 + ... + 8817946.

It is an arithmetic number, because the mean of its divisors is an integer number (2918521666).

Almost surely, 2^11656451431 is an apocalyptic number.

11656451431 is a deficient number, since it is larger than the sum of its proper divisors (17635233).

11656451431 is an equidigital number, since it uses as much as digits as its factorization.

11656451431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17635232.

The product of its digits is 43200, while the sum is 37.

The spelling of 11656451431 in words is "eleven billion, six hundred fifty-six million, four hundred fifty-one thousand, four hundred thirty-one".