8611517561 has 4 divisors (see below), whose sum is σ = 8985931392. Its totient is φ = 8237103732.

The previous prime is 8611517513. The next prime is 8611517567. The reversal of 8611517561 is 1657151168.

It is a happy number.

8611517561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 8611517561 - 2¹⁸ = 8611255417 is a prime.

It is a super-2 number, since 2×8611517561² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8611517567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 187206881 + ... + 187206926.

It is an arithmetic number, because the mean of its divisors is an integer number (2246482848).

Almost surely, 2^8611517561 is an apocalyptic number.

It is an amenable number.

8611517561 is a deficient number, since it is larger than the sum of its proper divisors (374413831).

8611517561 is a wasteful number, since it uses less digits than its factorization.

8611517561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374413830.

The product of its digits is 50400, while the sum is 41.

The square root of 8611517561 is about 92798.2627046433. The cubic root of 8611517561 is about 2049.7138256883.

The spelling of 8611517561 in words is "eight billion, six hundred eleven million, five hundred seventeen thousand, five hundred sixty-one".