391847 has 2 divisors, whose sum is σ = 391848. Its totient is φ = 391846.

The previous prime is 391823. The next prime is 391861. The reversal of 391847 is 748193.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391847 is a prime.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 391847.

It is not a weakly prime, because it can be changed into another prime (391817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195923 + 195924.

It is an arithmetic number, because the mean of its divisors is an integer number (195924).

2³⁹¹⁸⁴⁷ is an apocalyptic number.

391847 is a deficient number, since it is larger than the sum of its proper divisors (1).

391847 is an equidigital number, since it uses as much as digits as its factorization.

391847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 32.

The square root of 391847 is about 625.9768366322. The cubic root of 391847 is about 73.1765912986.

The spelling of 391847 in words is "three hundred ninety-one thousand, eight hundred forty-seven".