8915561663 has 4 divisors (see below), whose sum is σ = 8915752728. Its totient is φ = 8915370600.

The previous prime is 8915561659. The next prime is 8915561693. The reversal of 8915561663 is 3661655198.

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 8915561663 - 2² = 8915561659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8915561623) 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, 25988 + ... + 136038.

It is an arithmetic number, because the mean of its divisors is an integer number (2228938182).

Almost surely, 2^8915561663 is an apocalyptic number.

8915561663 is a deficient number, since it is larger than the sum of its proper divisors (191065).

8915561663 is a wasteful number, since it uses less digits than its factorization.

8915561663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191064.

The product of its digits is 1166400, while the sum is 50.

The square root of 8915561663 is about 94422.2519483623. The cubic root of 8915561663 is about 2073.5582310818.

The spelling of 8915561663 in words is "eight billion, nine hundred fifteen million, five hundred sixty-one thousand, six hundred sixty-three".