18372720 has 80 divisors (see below), whose sum is σ = 58523040. Its totient is φ = 4764672.

The previous prime is 18372719. The next prime is 18372721. The reversal of 18372720 is 2727381.

18372720 = 95² + 96² + ... + 382².

It is an interprime number because it is at equal distance from previous prime (18372719) and next prime (18372721).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18372721) 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, 7846 + ... + 9914.

It is an arithmetic number, because the mean of its divisors is an integer number (731538).

Almost surely, 2^18372720 is an apocalyptic number.

18372720 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 18372720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29261520).

18372720 is an abundant number, since it is smaller than the sum of its proper divisors (40150320).

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

18372720 is a wasteful number, since it uses less digits than its factorization.

18372720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2122 (or 2116 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 18372720 is about 4286.3410970197. The cubic root of 18372720 is about 263.8706896570.

The spelling of 18372720 in words is "eighteen million, three hundred seventy-two thousand, seven hundred twenty".