8155688661 has 16 divisors (see below), whose sum is σ = 12472261120. Its totient is φ = 5261734080.

The previous prime is 8155688621. The next prime is 8155688663. The reversal of 8155688661 is 1668865518.

8155688661 is a `hidden beast` number, since 8 + 1 + 556 + 8 + 86 + 6 + 1 = 666.

It is not a de Polignac number, because 8155688661 - 2¹⁰ = 8155687637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8155688598 and 8155688607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8155688663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4871140 + ... + 4872813.

It is an arithmetic number, because the mean of its divisors is an integer number (779516320).

Almost surely, 2^8155688661 is an apocalyptic number.

It is an amenable number.

8155688661 is a deficient number, since it is larger than the sum of its proper divisors (4316572459).

8155688661 is a wasteful number, since it uses less digits than its factorization.

8155688661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9743993 (or 9743987 counting only the distinct ones).

The product of its digits is 2764800, while the sum is 54.

The square root of 8155688661 is about 90308.8515096942. The cubic root of 8155688661 is about 2012.8907903377.

The spelling of 8155688661 in words is "eight billion, one hundred fifty-five million, six hundred eighty-eight thousand, six hundred sixty-one".