391340 has 24 divisors (see below), whose sum is σ = 870912. Its totient is φ = 147200.

The previous prime is 391337. The next prime is 391351. The reversal of 391340 is 43193.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable 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 in 7 ways as a sum of consecutive naturals, for example, 236 + ... + 915.

It is an arithmetic number, because the mean of its divisors is an integer number (36288).

2³⁹¹³⁴⁰ is an apocalyptic number.

It is an amenable number.

391340 is an abundant number, since it is smaller than the sum of its proper divisors (479572).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391340 is a wasteful number, since it uses less digits than its factorization.

391340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1177 (or 1175 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 391340 is about 625.5717384921. The cubic root of 391340 is about 73.1450172876.

It can be divided in two parts, 3913 and 40, that multiplied together give a triangular number (156520 = T₅₅₉).

The spelling of 391340 in words is "three hundred ninety-one thousand, three hundred forty".