18945811 has 2 divisors, whose sum is σ = 18945812. Its totient is φ = 18945810.

The previous prime is 18945799. The next prime is 18945821. The reversal of 18945811 is 11854981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18945811 - 2⁵ = 18945779 is a prime.

It is not a weakly prime, because it can be changed into another prime (18945821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9472905 + 9472906.

It is an arithmetic number, because the mean of its divisors is an integer number (9472906).

Almost surely, 2^18945811 is an apocalyptic number.

18945811 is a deficient number, since it is larger than the sum of its proper divisors (1).

18945811 is an equidigital number, since it uses as much as digits as its factorization.

18945811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 37.

The square root of 18945811 is about 4352.6786005861. The cubic root of 18945811 is about 266.5862425876.

The spelling of 18945811 in words is "eighteen million, nine hundred forty-five thousand, eight hundred eleven".