18113920 has 128 divisors (see below), whose sum is σ = 49351680. Its totient is φ = 6297600.

The previous prime is 18113881. The next prime is 18113929. The reversal of 18113920 is 2931181.

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

It is a super-2 number, since 2×18113920² = 656228195532800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18113929) 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, 218199 + ... + 218281.

It is an arithmetic number, because the mean of its divisors is an integer number (385560).

Almost surely, 2^18113920 is an apocalyptic number.

18113920 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 18113920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24675840).

18113920 is an abundant number, since it is smaller than the sum of its proper divisors (31237760).

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

18113920 is a wasteful number, since it uses less digits than its factorization.

18113920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 18113920 is about 4256.0451125429. The cubic root of 18113920 is about 262.6258565037.

The spelling of 18113920 in words is "eighteen million, one hundred thirteen thousand, nine hundred twenty".