16820320 has 96 divisors (see below), whose sum is σ = 45722880. Its totient is φ = 5783040.

The previous prime is 16820317. The next prime is 16820333. The reversal of 16820320 is 2302861.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 16820291 and 16820300.

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, 33189 + ... + 33691.

It is an arithmetic number, because the mean of its divisors is an integer number (476280).

It is a vampire number, since it can be written as 2012 ⋅ 8360 (with its own digits).

Almost surely, 2^16820320 is an apocalyptic number.

16820320 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 16820320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22861440).

16820320 is an abundant number, since it is smaller than the sum of its proper divisors (28902560).

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

16820320 is a wasteful number, since it uses less digits than its factorization.

16820320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 540 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 16820320 is about 4101.2583434844. The cubic root of 16820320 is about 256.2190507932.

It can be divided in two parts, 16820 and 320, that multiplied together give a square (5382400 = 2320²).

The spelling of 16820320 in words is "sixteen million, eight hundred twenty thousand, three hundred twenty".