16520720 has 40 divisors (see below), whose sum is σ = 39740760. Its totient is φ = 6379520.

The previous prime is 16520711. The next prime is 16520741. The reversal of 16520720 is 2702561.

It can be written as a sum of positive squares in 4 ways, for example, as 4624 + 16516096 = 68^2 + 4064^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1241 + ... + 5880.

It is an arithmetic number, because the mean of its divisors is an integer number (993519).

Almost surely, 2^16520720 is an apocalyptic number.

16520720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16520720 is an abundant number, since it is smaller than the sum of its proper divisors (23220040).

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

16520720 is a wasteful number, since it uses less digits than its factorization.

16520720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7163 (or 7157 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 16520720 is about 4064.5688578249. The cubic root of 16520720 is about 254.6886884033.

The spelling of 16520720 in words is "sixteen million, five hundred twenty thousand, seven hundred twenty".