17994779 has 4 divisors (see below), whose sum is σ = 19630680. Its totient is φ = 16358880.

The previous prime is 17994731. The next prime is 17994791. The reversal of 17994779 is 97749971.

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 17994779 - 2²⁰ = 16946203 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 17994779.

It is not an unprimeable number, because it can be changed into a prime (17994709) 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, 817934 + ... + 817955.

It is an arithmetic number, because the mean of its divisors is an integer number (4907670).

Almost surely, 2^17994779 is an apocalyptic number.

17994779 is a deficient number, since it is larger than the sum of its proper divisors (1635901).

17994779 is a wasteful number, since it uses less digits than its factorization.

17994779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1635900.

The product of its digits is 1000188, while the sum is 53.

The square root of 17994779 is about 4242.0253417442. The cubic root of 17994779 is about 262.0487982839.

The spelling of 17994779 in words is "seventeen million, nine hundred ninety-four thousand, seven hundred seventy-nine".