13551113561 has 4 divisors (see below), whose sum is σ = 13551358224. Its totient is φ = 13550868900.

The previous prime is 13551113549. The next prime is 13551113623. The reversal of 13551113561 is 16531115531.

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: 16531115531 = 7 ⋅2361587933.

It is a cyclic number.

It is not a de Polignac number, because 13551113561 - 2²² = 13546919257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13551113161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4766 + ... + 164696.

It is an arithmetic number, because the mean of its divisors is an integer number (3387839556).

Almost surely, 2^13551113561 is an apocalyptic number.

It is an amenable number.

13551113561 is a deficient number, since it is larger than the sum of its proper divisors (244663).

13551113561 is an equidigital number, since it uses as much as digits as its factorization.

13551113561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244662.

The product of its digits is 6750, while the sum is 32.

The spelling of 13551113561 in words is "thirteen billion, five hundred fifty-one million, one hundred thirteen thousand, five hundred sixty-one".