391390 has 8 divisors (see below), whose sum is σ = 704520. Its totient is φ = 156552.

The previous prime is 391387. The next prime is 391393. The reversal of 391390 is 93193.

It is an interprime number because it is at equal distance from previous prime (391387) and next prime (391393).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×391390² = 306372264200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391393) 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 in 3 ways as a sum of consecutive naturals, for example, 19560 + ... + 19579.

It is an arithmetic number, because the mean of its divisors is an integer number (88065).

2³⁹¹³⁹⁰ is an apocalyptic number.

391390 is a deficient number, since it is larger than the sum of its proper divisors (313130).

391390 is a wasteful number, since it uses less digits than its factorization.

391390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39146.

The product of its (nonzero) digits is 729, while the sum is 25.

The square root of 391390 is about 625.6117006578. The cubic root of 391390 is about 73.1481323071.

It can be divided in two parts, 3 and 91390, that multiplied together give a triangular number (274170 = T₇₄₀).

The spelling of 391390 in words is "three hundred ninety-one thousand, three hundred ninety".