391793138 has 8 divisors (see below), whose sum is σ = 641116080. Its totient is φ = 178087780.

The previous prime is 391793137. The next prime is 391793173. The reversal of 391793138 is 831397193.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (391793131) 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, 8904368 + ... + 8904411.

It is an arithmetic number, because the mean of its divisors is an integer number (80139510).

Almost surely, 2^391793138 is an apocalyptic number.

391793138 is a deficient number, since it is larger than the sum of its proper divisors (249322942).

391793138 is a wasteful number, since it uses less digits than its factorization.

391793138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17808792.

The product of its digits is 122472, while the sum is 44.

The square root of 391793138 is about 19793.7651294543. The cubic root of 391793138 is about 731.7323827375.

The spelling of 391793138 in words is "three hundred ninety-one million, seven hundred ninety-three thousand, one hundred thirty-eight".