391090 has 32 divisors (see below), whose sum is σ = 831744. Its totient is φ = 129600.

The previous prime is 391073. The next prime is 391103. The reversal of 391090 is 90193.

It is an unprimeable number.

391090 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 15 ways as a sum of consecutive naturals, for example, 2515 + ... + 2665.

It is an arithmetic number, because the mean of its divisors is an integer number (25992).

2³⁹¹⁰⁹⁰ is an apocalyptic number.

391090 is an abundant number, since it is smaller than the sum of its proper divisors (440654).

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

391090 is a wasteful number, since it uses less digits than its factorization.

391090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202.

The product of its (nonzero) digits is 243, while the sum is 22.

The square root of 391090 is about 625.3718893586. The cubic root of 391090 is about 73.1294382092.

The spelling of 391090 in words is "three hundred ninety-one thousand, ninety".