15561716051 has 4 divisors (see below), whose sum is σ = 17784818352. Its totient is φ = 13338613752.

The previous prime is 15561716011. The next prime is 15561716057. The reversal of 15561716051 is 15061716551.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 15561716051 - 2¹⁸ = 15561453907 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 15561715996 and 15561716014.

It is not an unprimeable number, because it can be changed into a prime (15561716057) 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, 1111551140 + ... + 1111551153.

It is an arithmetic number, because the mean of its divisors is an integer number (4446204588).

Almost surely, 2^15561716051 is an apocalyptic number.

15561716051 is a deficient number, since it is larger than the sum of its proper divisors (2223102301).

15561716051 is an equidigital number, since it uses as much as digits as its factorization.

15561716051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2223102300.

The product of its (nonzero) digits is 31500, while the sum is 38.

The spelling of 15561716051 in words is "fifteen billion, five hundred sixty-one million, seven hundred sixteen thousand, fifty-one".