18331380 has 96 divisors (see below), whose sum is σ = 57859200. Its totient is φ = 4817664.

The previous prime is 18331367. The next prime is 18331381. The reversal of 18331380 is 8313381.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18331381) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44616 + ... + 45024.

It is an arithmetic number, because the mean of its divisors is an integer number (602700).

Almost surely, 2^18331380 is an apocalyptic number.

18331380 is a gapful number since it is divisible by the number (10) 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 18331380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28929600).

18331380 is an abundant number, since it is smaller than the sum of its proper divisors (39527820).

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

18331380 is a wasteful number, since it uses less digits than its factorization.

18331380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 510 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 18331380 is about 4281.5160866217. The cubic root of 18331380 is about 263.6726314102.

The spelling of 18331380 in words is "eighteen million, three hundred thirty-one thousand, three hundred eighty".