18201091 has 2 divisors, whose sum is σ = 18201092. Its totient is φ = 18201090.

The previous prime is 18201059. The next prime is 18201097. The reversal of 18201091 is 19010281.

It is a strong prime.

It is an emirp because it is prime and its reverse (19010281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18201091 - 2⁵ = 18201059 is a prime.

It is not a weakly prime, because it can be changed into another prime (18201097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9100545 + 9100546.

It is an arithmetic number, because the mean of its divisors is an integer number (9100546).

Almost surely, 2^18201091 is an apocalyptic number.

18201091 is a deficient number, since it is larger than the sum of its proper divisors (1).

18201091 is an equidigital number, since it uses as much as digits as its factorization.

18201091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 18201091 is about 4266.2736667964. The cubic root of 18201091 is about 263.0464673302.

The spelling of 18201091 in words is "eighteen million, two hundred one thousand, ninety-one".