16509680 has 80 divisors (see below), whose sum is σ = 42613344. Its totient is φ = 5898240.

The previous prime is 16509673. The next prime is 16509719. The reversal of 16509680 is 8690561.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 16509680.

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, 64112 + ... + 64368.

Almost surely, 2^16509680 is an apocalyptic number.

16509680 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 16509680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21306672).

16509680 is an abundant number, since it is smaller than the sum of its proper divisors (26103664).

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

16509680 is a wasteful number, since it uses less digits than its factorization.

16509680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 16509680 is about 4063.2105532448. The cubic root of 16509680 is about 254.6319437078.

The spelling of 16509680 in words is "sixteen million, five hundred nine thousand, six hundred eighty".