5161561556 has 24 divisors (see below), whose sum is σ = 9594665640. Its totient is φ = 2421199872.

The previous prime is 5161561541. The next prime is 5161561567. The reversal of 5161561556 is 6551651615.

It can be written as a sum of positive squares in 4 ways, for example, as 386751556 + 4774810000 = 19666^2 + 69100^2 .

It is a super-2 number, since 2×5161561556² = 53283435392754282272, which contains 22 as substring.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99971 + ... + 142538.

It is an arithmetic number, because the mean of its divisors is an integer number (399777735).

Almost surely, 2^5161561556 is an apocalyptic number.

It is an amenable number.

5161561556 is a deficient number, since it is larger than the sum of its proper divisors (4433104084).

5161561556 is a wasteful number, since it uses less digits than its factorization.

5161561556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242843 (or 242841 counting only the distinct ones).

The product of its digits is 135000, while the sum is 41.

The square root of 5161561556 is about 71844.0084906181. The cubic root of 5161561556 is about 1728.1988176624.

The spelling of 5161561556 in words is "five billion, one hundred sixty-one million, five hundred sixty-one thousand, five hundred fifty-six".