18989964 has 72 divisors (see below), whose sum is σ = 56912128. Its totient is φ = 5423760.

The previous prime is 18989959. The next prime is 18990017. The reversal of 18989964 is 46998981.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 18989964.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5409 + ... + 8199.

Almost surely, 2^18989964 is an apocalyptic number.

18989964 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18989964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28456064).

18989964 is an abundant number, since it is smaller than the sum of its proper divisors (37922164).

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

18989964 is a wasteful number, since it uses less digits than its factorization.

18989964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2817 (or 2803 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 54.

The square root of 18989964 is about 4357.7475833279. The cubic root of 18989964 is about 266.7931740029.

It can be divided in two parts, 189 and 89964, that multiplied together give a triangular number (17003196 = T₅₈₃₁).

The spelling of 18989964 in words is "eighteen million, nine hundred eighty-nine thousand, nine hundred sixty-four".