5161515561 has 16 divisors (see below), whose sum is σ = 7652120320. Its totient is φ = 3438566640.

The previous prime is 5161515551. The next prime is 5161515587. The reversal of 5161515561 is 1655151615.

It is a happy number.

5161515561 is a `hidden beast` number, since 51 + 6 + 1 + 51 + 556 + 1 = 666.

It is not a de Polignac number, because 5161515561 - 2⁵ = 5161515529 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (5161515511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28750 + ... + 105591.

It is an arithmetic number, because the mean of its divisors is an integer number (478257520).

Almost surely, 2^5161515561 is an apocalyptic number.

It is an amenable number.

5161515561 is a deficient number, since it is larger than the sum of its proper divisors (2490604759).

5161515561 is a wasteful number, since it uses less digits than its factorization.

5161515561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135773 (or 135767 counting only the distinct ones).

The product of its digits is 22500, while the sum is 36.

The square root of 5161515561 is about 71843.6883866634. The cubic root of 5161515561 is about 1728.1936842843.

It can be divided in two parts, 51615 and 15561, that added together give a palindrome (67176).

The spelling of 5161515561 in words is "five billion, one hundred sixty-one million, five hundred fifteen thousand, five hundred sixty-one".