18611717657 has 8 divisors (see below), whose sum is σ = 21222411336. Its totient is φ = 16169455872.

The previous prime is 18611717651. The next prime is 18611717717. The reversal of 18611717657 is 75671711681.

It can be written as a sum of positive squares in 4 ways, for example, as 1861145881 + 16750571776 = 43141^2 + 129424^2 .

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 18611717657 - 2⁸ = 18611717401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18611717651) 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, 42107738 + ... + 42108179.

It is an arithmetic number, because the mean of its divisors is an integer number (2652801417).

Almost surely, 2^18611717657 is an apocalyptic number.

18611717657 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18611717657 is a deficient number, since it is larger than the sum of its proper divisors (2610693679).

18611717657 is a wasteful number, since it uses less digits than its factorization.

18611717657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84215947.

The product of its digits is 493920, while the sum is 50.

The spelling of 18611717657 in words is "eighteen billion, six hundred eleven million, seven hundred seventeen thousand, six hundred fifty-seven".