391265 has 12 divisors (see below), whose sum is σ = 546516. Its totient is φ = 268128.

The previous prime is 391249. The next prime is 391273. The reversal of 391265 is 562193.

391265 = 8² + 9² + ... + 105².

It can be written as a sum of positive squares in 2 ways, for example, as 108241 + 283024 = 329^2 + 532^2 .

It is not a de Polignac number, because 391265 - 2⁴ = 391249 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 554 + ... + 1043.

It is an arithmetic number, because the mean of its divisors is an integer number (45543).

2³⁹¹²⁶⁵ is an apocalyptic number.

391265 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

391265 is a deficient number, since it is larger than the sum of its proper divisors (155251).

391265 is a wasteful number, since it uses less digits than its factorization.

391265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1616 (or 1609 counting only the distinct ones).

The product of its digits is 1620, while the sum is 26.

The square root of 391265 is about 625.5117904564. The cubic root of 391265 is about 73.1403442609.

It can be divided in two parts, 391 and 265, that added together give a palindrome (656).

The spelling of 391265 in words is "three hundred ninety-one thousand, two hundred sixty-five".