16509920 has 48 divisors (see below), whose sum is σ = 44579808. Its totient is φ = 5660160.

The previous prime is 16509919. The next prime is 16509931. The reversal of 16509920 is 2990561.

It is a Harshad number since it is a multiple of its sum of digits (32).

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, 6251 + ... + 8490.

It is an arithmetic number, because the mean of its divisors is an integer number (928746).

Almost surely, 2^16509920 is an apocalyptic number.

16509920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16509920 is an abundant number, since it is smaller than the sum of its proper divisors (28069888).

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

16509920 is a wasteful number, since it uses less digits than its factorization.

16509920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14763 (or 14755 counting only the distinct ones).

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 16509920 is about 4063.2400864335. The cubic root of 16509920 is about 254.6331775571.

The spelling of 16509920 in words is "sixteen million, five hundred nine thousand, nine hundred twenty".