18716531 has 2 divisors, whose sum is σ = 18716532. Its totient is φ = 18716530.

The previous prime is 18716527. The next prime is 18716557. The reversal of 18716531 is 13561781.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18716531 - 2² = 18716527 is a prime.

It is a super-2 number, since 2×18716531² = 700617065347922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18716231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9358265 + 9358266.

It is an arithmetic number, because the mean of its divisors is an integer number (9358266).

Almost surely, 2^18716531 is an apocalyptic number.

18716531 is a deficient number, since it is larger than the sum of its proper divisors (1).

18716531 is an equidigital number, since it uses as much as digits as its factorization.

18716531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 32.

The square root of 18716531 is about 4326.2606255287. The cubic root of 18716531 is about 265.5064765060.

The spelling of 18716531 in words is "eighteen million, seven hundred sixteen thousand, five hundred thirty-one".