391123 has 4 divisors (see below), whose sum is σ = 404640. Its totient is φ = 377608.

The previous prime is 391117. The next prime is 391133. The reversal of 391123 is 321193.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391123 is a prime.

It is a super-2 number, since 2×391123² = 305954402258, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 391123.

It is not an unprimeable number, because it can be changed into a prime (391103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6715 + ... + 6772.

It is an arithmetic number, because the mean of its divisors is an integer number (101160).

2³⁹¹¹²³ is an apocalyptic number.

391123 is a deficient number, since it is larger than the sum of its proper divisors (13517).

391123 is a wasteful number, since it uses less digits than its factorization.

391123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13516.

The product of its digits is 162, while the sum is 19.

The square root of 391123 is about 625.3982731028. The cubic root of 391123 is about 73.1314950278.

The spelling of 391123 in words is "three hundred ninety-one thousand, one hundred twenty-three".