18863988 has 48 divisors (see below), whose sum is σ = 51715776. Its totient is φ = 5276160.

The previous prime is 18863987. The next prime is 18864023. The reversal of 18863988 is 88936881.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18863988.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18863987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3781 + ... + 7212.

It is an arithmetic number, because the mean of its divisors is an integer number (1077412).

Almost surely, 2^18863988 is an apocalyptic number.

It is an amenable number.

18863988 is an abundant number, since it is smaller than the sum of its proper divisors (32851788).

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

18863988 is a wasteful number, since it uses less digits than its factorization.

18863988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11024 (or 11022 counting only the distinct ones).

The product of its digits is 663552, while the sum is 51.

The square root of 18863988 is about 4343.2692755573. The cubic root of 18863988 is about 266.2019120100.

The spelling of 18863988 in words is "eighteen million, eight hundred sixty-three thousand, nine hundred eighty-eight".