18943720 has 64 divisors (see below), whose sum is σ = 45360000. Its totient is φ = 7104768.

The previous prime is 18943669. The next prime is 18943747. The reversal of 18943720 is 2734981.

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, 54106 + ... + 54454.

It is an arithmetic number, because the mean of its divisors is an integer number (708750).

Almost surely, 2^18943720 is an apocalyptic number.

18943720 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 18943720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22680000).

18943720 is an abundant number, since it is smaller than the sum of its proper divisors (26416280).

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

18943720 is a wasteful number, since it uses less digits than its factorization.

18943720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442 (or 438 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 18943720 is about 4352.4383970368. The cubic root of 18943720 is about 266.5764347495.

The spelling of 18943720 in words is "eighteen million, nine hundred forty-three thousand, seven hundred twenty".