18873887 has 2 divisors, whose sum is σ = 18873888. Its totient is φ = 18873886.

The previous prime is 18873871. The next prime is 18873889. The reversal of 18873887 is 78837881.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18873887 - 2⁴ = 18873871 is a prime.

It is a super-2 number, since 2×18873887² = 712447220977538, which contains 22 as substring.

Together with 18873889, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18873889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9436943 + 9436944.

It is an arithmetic number, because the mean of its divisors is an integer number (9436944).

Almost surely, 2^18873887 is an apocalyptic number.

18873887 is a deficient number, since it is larger than the sum of its proper divisors (1).

18873887 is an equidigital number, since it uses as much as digits as its factorization.

18873887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 602112, while the sum is 50.

The square root of 18873887 is about 4344.4087054512. The cubic root of 18873887 is about 266.2484675939.

The spelling of 18873887 in words is "eighteen million, eight hundred seventy-three thousand, eight hundred eighty-seven".