8563765661 has 8 divisors (see below), whose sum is σ = 9495442848. Its totient is φ = 7657614000.

The previous prime is 8563765631. The next prime is 8563765669. The reversal of 8563765661 is 1665673658.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8563765661 - 2⁶ = 8563765597 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 (8563765669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6380675 + ... + 6382016.

It is an arithmetic number, because the mean of its divisors is an integer number (1186930356).

Almost surely, 2^8563765661 is an apocalyptic number.

It is an amenable number.

8563765661 is a deficient number, since it is larger than the sum of its proper divisors (931677187).

8563765661 is a wasteful number, since it uses less digits than its factorization.

8563765661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12762763.

The product of its digits is 5443200, while the sum is 53.

The square root of 8563765661 is about 92540.6162773947. The cubic root of 8563765661 is about 2045.9181647056.

The spelling of 8563765661 in words is "eight billion, five hundred sixty-three million, seven hundred sixty-five thousand, six hundred sixty-one".