18368990947 has 2 divisors, whose sum is σ = 18368990948. Its totient is φ = 18368990946.

The previous prime is 18368990923. The next prime is 18368990951. The reversal of 18368990947 is 74909986381.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18368990947 - 2¹⁹ = 18368466659 is a prime.

It is not a weakly prime, because it can be changed into another prime (18368993947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9184495473 + 9184495474.

It is an arithmetic number, because the mean of its divisors is an integer number (9184495474).

Almost surely, 2^18368990947 is an apocalyptic number.

18368990947 is a deficient number, since it is larger than the sum of its proper divisors (1).

18368990947 is an equidigital number, since it uses as much as digits as its factorization.

18368990947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23514624, while the sum is 64.

The spelling of 18368990947 in words is "eighteen billion, three hundred sixty-eight million, nine hundred ninety thousand, nine hundred forty-seven".