391844 has 6 divisors (see below), whose sum is σ = 685734. Its totient is φ = 195920.

The previous prime is 391823. The next prime is 391847. The reversal of 391844 is 448193.

It can be written as a sum of positive squares in only one way, i.e., 289444 + 102400 = 538^2 + 320^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 391844.

It is not an unprimeable number, because it can be changed into a prime (391847) by changing a digit.

391844 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48977 + ... + 48984.

It is an arithmetic number, because the mean of its divisors is an integer number (114289).

2³⁹¹⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

391844 is a deficient number, since it is larger than the sum of its proper divisors (293890).

391844 is a wasteful number, since it uses less digits than its factorization.

391844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97965 (or 97963 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 391844 is about 625.9744403728. The cubic root of 391844 is about 73.1764045502.

The spelling of 391844 in words is "three hundred ninety-one thousand, eight hundred forty-four".