18645057947 has 2 divisors, whose sum is σ = 18645057948. Its totient is φ = 18645057946.

The previous prime is 18645057901. The next prime is 18645057961. The reversal of 18645057947 is 74975054681.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18645057947 - 2⁶ = 18645057883 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18645057892 and 18645057901.

It is not a weakly prime, because it can be changed into another prime (18645059947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9322528973 + 9322528974.

It is an arithmetic number, because the mean of its divisors is an integer number (9322528974).

Almost surely, 2^18645057947 is an apocalyptic number.

18645057947 is a deficient number, since it is larger than the sum of its proper divisors (1).

18645057947 is an equidigital number, since it uses as much as digits as its factorization.

18645057947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8467200, while the sum is 56.

The spelling of 18645057947 in words is "eighteen billion, six hundred forty-five million, fifty-seven thousand, nine hundred forty-seven".