18047191 has 2 divisors, whose sum is σ = 18047192. Its totient is φ = 18047190.

The previous prime is 18047179. The next prime is 18047209. The reversal of 18047191 is 19174081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18047191 - 2⁷ = 18047063 is a prime.

It is a super-2 number, since 2×18047191² = 651402205980962, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18047291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9023595 + 9023596.

It is an arithmetic number, because the mean of its divisors is an integer number (9023596).

Almost surely, 2^18047191 is an apocalyptic number.

18047191 is a deficient number, since it is larger than the sum of its proper divisors (1).

18047191 is an equidigital number, since it uses as much as digits as its factorization.

18047191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 18047191 is about 4248.1985593896. The cubic root of 18047191 is about 262.3029680939.

The spelling of 18047191 in words is "eighteen million, forty-seven thousand, one hundred ninety-one".