18887859 has 6 divisors (see below), whose sum is σ = 27282476. Its totient is φ = 12591900.

The previous prime is 18887851. The next prime is 18887861. The reversal of 18887859 is 95878881.

It is not a de Polignac number, because 18887859 - 2³ = 18887851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18887851) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1049317 + ... + 1049334.

Almost surely, 2^18887859 is an apocalyptic number.

18887859 is a deficient number, since it is larger than the sum of its proper divisors (8394617).

18887859 is a wasteful number, since it uses less digits than its factorization.

18887859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2098657 (or 2098654 counting only the distinct ones).

The product of its digits is 1290240, while the sum is 54.

The square root of 18887859 is about 4346.0164518787. The cubic root of 18887859 is about 266.3141510434.

The spelling of 18887859 in words is "eighteen million, eight hundred eighty-seven thousand, eight hundred fifty-nine".