18821376 has 144 divisors (see below), whose sum is σ = 63772800. Its totient is φ = 5363712.

The previous prime is 18821353. The next prime is 18821389. The reversal of 18821376 is 67312881.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 18821376.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48190 + ... + 48578.

Almost surely, 2^18821376 is an apocalyptic number.

18821376 is a gapful number since it is divisible by the number (16) 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 18821376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31886400).

18821376 is an abundant number, since it is smaller than the sum of its proper divisors (44951424).

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

18821376 is an equidigital number, since it uses as much as digits as its factorization.

18821376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421 (or 401 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 18821376 is about 4338.3609808314. The cubic root of 18821376 is about 266.0013190807.

The spelling of 18821376 in words is "eighteen million, eight hundred twenty-one thousand, three hundred seventy-six".