18045491 has 2 divisors, whose sum is σ = 18045492. Its totient is φ = 18045490.

The previous prime is 18045473. The next prime is 18045541. The reversal of 18045491 is 19454081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18045491 - 2⁶ = 18045427 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18045451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9022745 + 9022746.

It is an arithmetic number, because the mean of its divisors is an integer number (9022746).

Almost surely, 2^18045491 is an apocalyptic number.

18045491 is a deficient number, since it is larger than the sum of its proper divisors (1).

18045491 is an equidigital number, since it uses as much as digits as its factorization.

18045491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 18045491 is about 4247.9984698679. The cubic root of 18045491 is about 262.2947317420.

The spelling of 18045491 in words is "eighteen million, forty-five thousand, four hundred ninety-one".