18910385677 has 2 divisors, whose sum is σ = 18910385678. Its totient is φ = 18910385676.

The previous prime is 18910385629. The next prime is 18910385713. The reversal of 18910385677 is 77658301981.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15561564516 + 3348821161 = 124746^2 + 57869^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18910385677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18910385477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9455192838 + 9455192839.

It is an arithmetic number, because the mean of its divisors is an integer number (9455192839).

Almost surely, 2^18910385677 is an apocalyptic number.

It is an amenable number.

18910385677 is a deficient number, since it is larger than the sum of its proper divisors (1).

18910385677 is an equidigital number, since it uses as much as digits as its factorization.

18910385677 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2540160, while the sum is 55.

The spelling of 18910385677 in words is "eighteen billion, nine hundred ten million, three hundred eighty-five thousand, six hundred seventy-seven".