16727980565 has 4 divisors (see below), whose sum is σ = 20073576684. Its totient is φ = 13382384448.

The previous prime is 16727980559. The next prime is 16727980601. The reversal of 16727980565 is 56508972761.

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 11524666609 + 5203313956 = 107353^2 + 72134^2 .

It is a cyclic number.

It is not a de Polignac number, because 16727980565 - 2⁸ = 16727980309 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16727980565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1672798052 + ... + 1672798061.

It is an arithmetic number, because the mean of its divisors is an integer number (5018394171).

Almost surely, 2^16727980565 is an apocalyptic number.

It is an amenable number.

16727980565 is a deficient number, since it is larger than the sum of its proper divisors (3345596119).

16727980565 is an equidigital number, since it uses as much as digits as its factorization.

16727980565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3345596118.

The product of its (nonzero) digits is 6350400, while the sum is 56.

The spelling of 16727980565 in words is "sixteen billion, seven hundred twenty-seven million, nine hundred eighty thousand, five hundred sixty-five".