18446720 has 128 divisors (see below), whose sum is σ = 48837600. Its totient is φ = 6635520.

The previous prime is 18446711. The next prime is 18446773. The reversal of 18446720 is 2764481.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (32).

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, 449900 + ... + 449940.

Almost surely, 2^18446720 is an apocalyptic number.

18446720 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 18446720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24418800).

18446720 is an abundant number, since it is smaller than the sum of its proper divisors (30390880).

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

18446720 is a wasteful number, since it uses less digits than its factorization.

18446720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 18446720 is about 4294.9644934504. The cubic root of 18446720 is about 264.2244800218.

The spelling of 18446720 in words is "eighteen million, four hundred forty-six thousand, seven hundred twenty".