18085631 has 2 divisors, whose sum is σ = 18085632. Its totient is φ = 18085630.

The previous prime is 18085609. The next prime is 18085649. The reversal of 18085631 is 13658081.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18085631 - 2²² = 13891327 is a prime.

It is a super-2 number, since 2×18085631² = 654180097336322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18085831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9042815 + 9042816.

It is an arithmetic number, because the mean of its divisors is an integer number (9042816).

Almost surely, 2^18085631 is an apocalyptic number.

18085631 is a deficient number, since it is larger than the sum of its proper divisors (1).

18085631 is an equidigital number, since it uses as much as digits as its factorization.

18085631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 18085631 is about 4252.7204234466. The cubic root of 18085631 is about 262.4890686302.

The spelling of 18085631 in words is "eighteen million, eighty-five thousand, six hundred thirty-one".