18508811 has 2 divisors, whose sum is σ = 18508812. Its totient is φ = 18508810.

The previous prime is 18508783. The next prime is 18508871. The reversal of 18508811 is 11880581.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18508811 - 2⁶ = 18508747 is a prime.

It is not a weakly prime, because it can be changed into another prime (18508871) 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, 9254405 + 9254406.

It is an arithmetic number, because the mean of its divisors is an integer number (9254406).

Almost surely, 2^18508811 is an apocalyptic number.

18508811 is a deficient number, since it is larger than the sum of its proper divisors (1).

18508811 is an equidigital number, since it uses as much as digits as its factorization.

18508811 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2560, while the sum is 32.

The square root of 18508811 is about 4302.1867695394. The cubic root of 18508811 is about 264.5206047392.

The spelling of 18508811 in words is "eighteen million, five hundred eight thousand, eight hundred eleven".