18112720 has 20 divisors (see below), whose sum is σ = 42112260. Its totient is φ = 7245056.

The previous prime is 18112663. The next prime is 18112727. The reversal of 18112720 is 2721181.

It can be written as a sum of positive squares in 2 ways, for example, as 13601344 + 4511376 = 3688^2 + 2124^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 18112691 and 18112700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18112727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113125 + ... + 113284.

It is an arithmetic number, because the mean of its divisors is an integer number (2105613).

Almost surely, 2^18112720 is an apocalyptic number.

18112720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18112720 is an abundant number, since it is smaller than the sum of its proper divisors (23999540).

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

18112720 is a wasteful number, since it uses less digits than its factorization.

18112720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226422 (or 226416 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 22.

The square root of 18112720 is about 4255.9041342587. The cubic root of 18112720 is about 262.6200569494.

The spelling of 18112720 in words is "eighteen million, one hundred twelve thousand, seven hundred twenty".