391447894 has 4 divisors (see below), whose sum is σ = 587171844. Its totient is φ = 195723946.

The previous prime is 391447891. The next prime is 391447897. The reversal of 391447894 is 498744193.

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

It is an interprime number because it is at equal distance from previous prime (391447891) and next prime (391447897).

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391447891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97861972 + ... + 97861975.

It is an arithmetic number, because the mean of its divisors is an integer number (146792961).

Almost surely, 2^391447894 is an apocalyptic number.

391447894 is a deficient number, since it is larger than the sum of its proper divisors (195723950).

391447894 is a wasteful number, since it uses less digits than its factorization.

391447894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195723949.

The product of its digits is 870912, while the sum is 49.

The square root of 391447894 is about 19785.0421783730. The cubic root of 391447894 is about 731.5173879435.

The spelling of 391447894 in words is "three hundred ninety-one million, four hundred forty-seven thousand, eight hundred ninety-four".