18625889 has 2 divisors, whose sum is σ = 18625890. Its totient is φ = 18625888.

The previous prime is 18625879. The next prime is 18625907. The reversal of 18625889 is 98852681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15147664 + 3478225 = 3892^2 + 1865^2 .

It is a cyclic number.

It is not a de Polignac number, because 18625889 - 2²⁴ = 1848673 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18625819) 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, 9312944 + 9312945.

It is an arithmetic number, because the mean of its divisors is an integer number (9312945).

Almost surely, 2^18625889 is an apocalyptic number.

It is an amenable number.

18625889 is a deficient number, since it is larger than the sum of its proper divisors (1).

18625889 is an equidigital number, since it uses as much as digits as its factorization.

18625889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 276480, while the sum is 47.

The square root of 18625889 is about 4315.7721209536. The cubic root of 18625889 is about 265.0771769991.

The spelling of 18625889 in words is "eighteen million, six hundred twenty-five thousand, eight hundred eighty-nine".