16981920 has 96 divisors (see below), whose sum is σ = 59451840. Its totient is φ = 4527360.

The previous prime is 16981903. The next prime is 16981931. The reversal of 16981920 is 2918961.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 2355 + ... + 6285.

It is an arithmetic number, because the mean of its divisors is an integer number (619290).

Almost surely, 2^16981920 is an apocalyptic number.

16981920 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 16981920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29725920).

16981920 is an abundant number, since it is smaller than the sum of its proper divisors (42469920).

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

16981920 is a wasteful number, since it uses less digits than its factorization.

16981920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3955 (or 3941 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 16981920 is about 4120.9125203042. The cubic root of 16981920 is about 257.0369722783.

The spelling of 16981920 in words is "sixteen million, nine hundred eighty-one thousand, nine hundred twenty".