391400 has 48 divisors (see below), whose sum is σ = 967200. Its totient is φ = 146880.

The previous prime is 391399. The next prime is 391403. The reversal of 391400 is 4193.

391400 = 3² + 4² + ... + 105².

It is not an unprimeable number, because it can be changed into a prime (391403) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 3749 + ... + 3851.

It is an arithmetic number, because the mean of its divisors is an integer number (20150).

2³⁹¹⁴⁰⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (483600).

391400 is an abundant number, since it is smaller than the sum of its proper divisors (575800).

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

391400 is a wasteful number, since it uses less digits than its factorization.

391400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 391400 is about 625.6196927847. The cubic root of 391400 is about 73.1487552791.

Adding to 391400 its reverse (4193), we get a palindrome (395593).

The spelling of 391400 in words is "three hundred ninety-one thousand, four hundred".