18220087 has 2 divisors, whose sum is σ = 18220088. Its totient is φ = 18220086.

The previous prime is 18220057. The next prime is 18220093. The reversal of 18220087 is 78002281.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18220087 - 2⁷ = 18219959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18220057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9110043 + 9110044.

It is an arithmetic number, because the mean of its divisors is an integer number (9110044).

Almost surely, 2^18220087 is an apocalyptic number.

18220087 is a deficient number, since it is larger than the sum of its proper divisors (1).

18220087 is an equidigital number, since it uses as much as digits as its factorization.

18220087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 18220087 is about 4268.4993850298. The cubic root of 18220087 is about 263.1379470725.

The spelling of 18220087 in words is "eighteen million, two hundred twenty thousand, eighty-seven".