391140 has 72 divisors (see below), whose sum is σ = 1238328. Its totient is φ = 99840.

The previous prime is 391133. The next prime is 391151. The reversal of 391140 is 41193.

It can be written as a sum of positive squares in 4 ways, for example, as 9216 + 381924 = 96^2 + 618^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

391140 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 (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7354 + ... + 7406.

It is an arithmetic number, because the mean of its divisors is an integer number (17199).

2³⁹¹¹⁴⁰ is an apocalyptic number.

391140 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (619164).

391140 is an abundant number, since it is smaller than the sum of its proper divisors (847188).

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

391140 is a wasteful number, since it uses less digits than its factorization.

391140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 391140 is about 625.4118642942. The cubic root of 391140 is about 73.1325545559.

The spelling of 391140 in words is "three hundred ninety-one thousand, one hundred forty".