15656551161 has 4 divisors (see below), whose sum is σ = 20875401552. Its totient is φ = 10437700772.

The previous prime is 15656551139. The next prime is 15656551177. The reversal of 15656551161 is 16115565651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16115565651 = 3 ⋅5371855217.

It is a cyclic number.

It is not a de Polignac number, because 15656551161 - 2⁵ = 15656551129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15656551111) 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, 2609425191 + ... + 2609425196.

It is an arithmetic number, because the mean of its divisors is an integer number (5218850388).

Almost surely, 2^15656551161 is an apocalyptic number.

It is an amenable number.

15656551161 is a deficient number, since it is larger than the sum of its proper divisors (5218850391).

15656551161 is an equidigital number, since it uses as much as digits as its factorization.

15656551161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5218850390.

The product of its digits is 135000, while the sum is 42.

The spelling of 15656551161 in words is "fifteen billion, six hundred fifty-six million, five hundred fifty-one thousand, one hundred sixty-one".