16618564779 has 4 divisors (see below), whose sum is σ = 22158086376. Its totient is φ = 11079043184.

The previous prime is 16618564769. The next prime is 16618564799. The reversal of 16618564779 is 97746581661.

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

It is a cyclic number.

It is not a de Polignac number, because 16618564779 - 2⁵ = 16618564747 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16618564709) 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, 2769760794 + ... + 2769760799.

It is an arithmetic number, because the mean of its divisors is an integer number (5539521594).

Almost surely, 2^16618564779 is an apocalyptic number.

16618564779 is a deficient number, since it is larger than the sum of its proper divisors (5539521597).

16618564779 is an equidigital number, since it uses as much as digits as its factorization.

16618564779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5539521596.

The product of its digits is 15240960, while the sum is 60.

The spelling of 16618564779 in words is "sixteen billion, six hundred eighteen million, five hundred sixty-four thousand, seven hundred seventy-nine".