18139087 has 2 divisors, whose sum is σ = 18139088. Its totient is φ = 18139086.

The previous prime is 18139073. The next prime is 18139103. The reversal of 18139087 is 78093181.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18139087 - 2⁷ = 18138959 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18139027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9069543 + 9069544.

It is an arithmetic number, because the mean of its divisors is an integer number (9069544).

Almost surely, 2^18139087 is an apocalyptic number.

18139087 is a deficient number, since it is larger than the sum of its proper divisors (1).

18139087 is an equidigital number, since it uses as much as digits as its factorization.

18139087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 18139087 is about 4259.0007043906. Note that the first 3 decimals coincide. The cubic root of 18139087 is about 262.7474286844.

The spelling of 18139087 in words is "eighteen million, one hundred thirty-nine thousand, eighty-seven".