18897984 has 168 divisors, whose sum is σ = 63926720. Its totient is φ = 5225472.

The previous prime is 18897971. The next prime is 18898037. The reversal of 18897984 is 48979881.

It is a tau number, because it is divible by the number of its divisors (168).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 18897984.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 173322 + ... + 173430.

Almost surely, 2^18897984 is an apocalyptic number.

18897984 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 18897984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31963360).

18897984 is an abundant number, since it is smaller than the sum of its proper divisors (45028736).

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

18897984 is a wasteful number, since it uses less digits than its factorization.

18897984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177 (or 164 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 54.

The square root of 18897984 is about 4347.1811556456. The cubic root of 18897984 is about 266.3617292100.

It can be divided in two parts, 18897 and 984, that added together give a square (19881 = 141²).

The spelling of 18897984 in words is "eighteen million, eight hundred ninety-seven thousand, nine hundred eighty-four".