18987992 has 32 divisors (see below), whose sum is σ = 38199600. Its totient is φ = 8820864.

The previous prime is 18987977. The next prime is 18988003. The reversal of 18987992 is 29978981.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6878 + ... + 9234.

Almost surely, 2^18987992 is an apocalyptic number.

It is an amenable number.

18987992 is an abundant number, since it is smaller than the sum of its proper divisors (19211608).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18987992 is a wasteful number, since it uses less digits than its factorization.

18987992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2435 (or 2431 counting only the distinct ones).

The product of its digits is 653184, while the sum is 53.

The square root of 18987992 is about 4357.5213137746. The cubic root of 18987992 is about 266.7839386975.

The spelling of 18987992 in words is "eighteen million, nine hundred eighty-seven thousand, nine hundred ninety-two".