16696199521 has 4 divisors (see below), whose sum is σ = 16696488852. Its totient is φ = 16695910192.

The previous prime is 16696199501. The next prime is 16696199561. The reversal of 16696199521 is 12599169661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1767025296 + 14929174225 = 42036^2 + 122185^2 .

It is a cyclic number.

It is not a de Polignac number, because 16696199521 - 2²⁵ = 16662645089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16696199501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25246 + ... + 184471.

It is an arithmetic number, because the mean of its divisors is an integer number (4174122213).

Almost surely, 2^16696199521 is an apocalyptic number.

It is an amenable number.

16696199521 is a deficient number, since it is larger than the sum of its proper divisors (289331).

16696199521 is an equidigital number, since it uses as much as digits as its factorization.

16696199521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289330.

The product of its digits is 1574640, while the sum is 55.

The spelling of 16696199521 in words is "sixteen billion, six hundred ninety-six million, one hundred ninety-nine thousand, five hundred twenty-one".