16688981596225 has 27 divisors (see below), whose sum is σ = 21187908107049. Its totient is φ = 13040006280000.

The previous prime is 16688981596207. The next prime is 16688981596253. The reversal of 16688981596225 is 52269518988661.

The square root of 16688981596225 is 4085215.

It is a perfect power (a square), and thus also a powerful number.

16688981596225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4184638918321 + 12504342677904 = 2045639^2 + 3536148^2 .

It is not a de Polignac number, because 16688981596225 - 2²⁵ = 16688948041793 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 878311725 + ... + 878330725.

Almost surely, 2^{16688981596225} is an apocalyptic number.

16688981596225 is the 4085215-th square number.

16688981596225 is the 2042608-th centered octagonal number.

It is an amenable number.

16688981596225 is a deficient number, since it is larger than the sum of its proper divisors (4498926510824).

16688981596225 is an frugal number, since it uses more digits than its factorization.

16688981596225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38098 (or 19049 counting only the distinct ones).

The product of its digits is 895795200, while the sum is 76.

The spelling of 16688981596225 in words is "sixteen trillion, six hundred eighty-eight billion, nine hundred eighty-one million, five hundred ninety-six thousand, two hundred twenty-five".