191979394 has 4 divisors (see below), whose sum is σ = 287969094. Its totient is φ = 95989696.

The previous prime is 191979371. The next prime is 191979397. The reversal of 191979394 is 493979191.

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

It can be written as a sum of positive squares in only one way, i.e., 143161225 + 48818169 = 11965^2 + 6987^2 .

It is not an unprimeable number, because it can be changed into a prime (191979397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 47994847 + ... + 47994850.

Almost surely, 2^191979394 is an apocalyptic number.

191979394 is a deficient number, since it is larger than the sum of its proper divisors (95989700).

191979394 is an equidigital number, since it uses as much as digits as its factorization.

191979394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95989699.

The product of its digits is 551124, while the sum is 52.

The square root of 191979394 is about 13855.6628856219. The cubic root of 191979394 is about 576.8791891939.

The spelling of 191979394 in words is "one hundred ninety-one million, nine hundred seventy-nine thousand, three hundred ninety-four".