18647932477 has 2 divisors, whose sum is σ = 18647932478. Its totient is φ = 18647932476.

The previous prime is 18647932453. The next prime is 18647932483. The reversal of 18647932477 is 77423974681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14726793316 + 3921139161 = 121354^2 + 62619^2 .

It is an emirp because it is prime and its reverse (77423974681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18647932477 - 2²⁷ = 18513714749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18647936477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9323966238 + 9323966239.

It is an arithmetic number, because the mean of its divisors is an integer number (9323966239).

Almost surely, 2^18647932477 is an apocalyptic number.

It is an amenable number.

18647932477 is a deficient number, since it is larger than the sum of its proper divisors (1).

18647932477 is an equidigital number, since it uses as much as digits as its factorization.

18647932477 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14224896, while the sum is 58.

The spelling of 18647932477 in words is "eighteen billion, six hundred forty-seven million, nine hundred thirty-two thousand, four hundred seventy-seven".