18157031 has 2 divisors, whose sum is σ = 18157032. Its totient is φ = 18157030.

The previous prime is 18157019. The next prime is 18157039. The reversal of 18157031 is 13075181.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18157031 - 2⁶ = 18156967 is a prime.

It is a super-2 number, since 2×18157031² = 659355549469922, 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 (18157039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9078515 + 9078516.

It is an arithmetic number, because the mean of its divisors is an integer number (9078516).

Almost surely, 2^18157031 is an apocalyptic number.

18157031 is a deficient number, since it is larger than the sum of its proper divisors (1).

18157031 is an equidigital number, since it uses as much as digits as its factorization.

18157031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 840, while the sum is 26.

The square root of 18157031 is about 4261.1067811075. The cubic root of 18157031 is about 262.8340406518.

The spelling of 18157031 in words is "eighteen million, one hundred fifty-seven thousand, thirty-one".