8817765661 has 8 divisors (see below), whose sum is σ = 9049723704. Its totient is φ = 8588236800.

The previous prime is 8817765659. The next prime is 8817765701. The reversal of 8817765661 is 1665677188.

It can be written as a sum of positive squares in 4 ways, for example, as 4810116025 + 4007649636 = 69355^2 + 63306^2 .

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 8817765661 - 2¹ = 8817765659 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 (8817765611) 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, 599940 + ... + 614461.

It is an arithmetic number, because the mean of its divisors is an integer number (1131215463).

Almost surely, 2^8817765661 is an apocalyptic number.

It is an amenable number.

8817765661 is a deficient number, since it is larger than the sum of its proper divisors (231958043).

8817765661 is a wasteful number, since it uses less digits than its factorization.

8817765661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1214591.

The product of its digits is 3386880, while the sum is 55.

The square root of 8817765661 is about 93902.9587446530. The cubic root of 8817765661 is about 2065.9486257036.

The spelling of 8817765661 in words is "eight billion, eight hundred seventeen million, seven hundred sixty-five thousand, six hundred sixty-one".