18315641 has 2 divisors, whose sum is σ = 18315642. Its totient is φ = 18315640.

The previous prime is 18315631. The next prime is 18315653. The reversal of 18315641 is 14651381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17682025 + 633616 = 4205^2 + 796^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18315641 is a prime.

It is not a weakly prime, because it can be changed into another prime (18315631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9157820 + 9157821.

It is an arithmetic number, because the mean of its divisors is an integer number (9157821).

Almost surely, 2^18315641 is an apocalyptic number.

It is an amenable number.

18315641 is a deficient number, since it is larger than the sum of its proper divisors (1).

18315641 is an equidigital number, since it uses as much as digits as its factorization.

18315641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 29.

The square root of 18315641 is about 4279.6776747788. The cubic root of 18315641 is about 263.5971482441.

The spelling of 18315641 in words is "eighteen million, three hundred fifteen thousand, six hundred forty-one".