16671199689 has 27 divisors (see below), whose sum is σ = 24315072327. Its totient is φ = 11006966016.

The previous prime is 16671199679. The next prime is 16671199709. The reversal of 16671199689 is 98699117661.

The square root of 16671199689 is 129117.

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

It can be written as a sum of positive squares in only one way, i.e., 4039238025 + 12631961664 = 63555^2 + 112392^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16671199689 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16671199609) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 74758632 + ... + 74758854.

Almost surely, 2^16671199689 is an apocalyptic number.

16671199689 is the 129117-th square number.

16671199689 is the 64559-th centered octagonal number.

It is an amenable number.

16671199689 is a deficient number, since it is larger than the sum of its proper divisors (7643872638).

16671199689 is an frugal number, since it uses more digits than its factorization.

16671199689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 838 (or 419 counting only the distinct ones).

The product of its digits is 8817984, while the sum is 63.

The spelling of 16671199689 in words is "sixteen billion, six hundred seventy-one million, one hundred ninety-nine thousand, six hundred eighty-nine".