18864887 has 2 divisors, whose sum is σ = 18864888. Its totient is φ = 18864886.

The previous prime is 18864871. The next prime is 18864959. The reversal of 18864887 is 78846881.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18864887 - 2⁴ = 18864871 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18864827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9432443 + 9432444.

It is an arithmetic number, because the mean of its divisors is an integer number (9432444).

Almost surely, 2^18864887 is an apocalyptic number.

18864887 is a deficient number, since it is larger than the sum of its proper divisors (1).

18864887 is an equidigital number, since it uses as much as digits as its factorization.

18864887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 688128, while the sum is 50.

The square root of 18864887 is about 4343.3727677923. The cubic root of 18864887 is about 266.2061407326.

The spelling of 18864887 in words is "eighteen million, eight hundred sixty-four thousand, eight hundred eighty-seven".