18638227 has 2 divisors, whose sum is σ = 18638228. Its totient is φ = 18638226.

The previous prime is 18638219. The next prime is 18638251. The reversal of 18638227 is 72283681.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18638227 - 2³ = 18638219 is a prime.

It is not a weakly prime, because it can be changed into another prime (18638267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9319113 + 9319114.

It is an arithmetic number, because the mean of its divisors is an integer number (9319114).

Almost surely, 2^18638227 is an apocalyptic number.

18638227 is a deficient number, since it is larger than the sum of its proper divisors (1).

18638227 is an equidigital number, since it uses as much as digits as its factorization.

18638227 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32256, while the sum is 37.

The square root of 18638227 is about 4317.2012925042. The cubic root of 18638227 is about 265.1356941225.

The spelling of 18638227 in words is "eighteen million, six hundred thirty-eight thousand, two hundred twenty-seven".