18682787971 has 2 divisors, whose sum is σ = 18682787972. Its totient is φ = 18682787970.

The previous prime is 18682787923. The next prime is 18682787987. The reversal of 18682787971 is 17978728681.

It is a strong prime.

It is an emirp because it is prime and its reverse (17978728681) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18682787971 is a prime.

It is not a weakly prime, because it can be changed into another prime (18682787471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9341393985 + 9341393986.

It is an arithmetic number, because the mean of its divisors is an integer number (9341393986).

Almost surely, 2^18682787971 is an apocalyptic number.

18682787971 is a deficient number, since it is larger than the sum of its proper divisors (1).

18682787971 is an equidigital number, since it uses as much as digits as its factorization.

18682787971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18966528, while the sum is 64.

The spelling of 18682787971 in words is "eighteen billion, six hundred eighty-two million, seven hundred eighty-seven thousand, nine hundred seventy-one".