394759979 has 4 divisors (see below), whose sum is σ = 415536840. Its totient is φ = 373983120.

The previous prime is 394759961. The next prime is 394759991. The reversal of 394759979 is 979957493.

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 394759979 - 2²⁰ = 393711403 is a prime.

It is a super-4 number, since 4×394759979⁴ (a number of 35 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (394759949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10388402 + ... + 10388439.

It is an arithmetic number, because the mean of its divisors is an integer number (103884210).

Almost surely, 2^394759979 is an apocalyptic number.

394759979 is a deficient number, since it is larger than the sum of its proper divisors (20776861).

394759979 is a wasteful number, since it uses less digits than its factorization.

394759979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20776860.

The product of its digits is 19289340, while the sum is 62.

The square root of 394759979 is about 19868.5676131925. The cubic root of 394759979 is about 733.5747468035.

The spelling of 394759979 in words is "three hundred ninety-four million, seven hundred fifty-nine thousand, nine hundred seventy-nine".