265989 has 4 divisors (see below), whose sum is σ = 354656. Its totient is φ = 177324.

The previous prime is 265987. The next prime is 266003. The reversal of 265989 is 989562.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 265989 - 2¹ = 265987 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (265987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44329 + ... + 44334.

It is an arithmetic number, because the mean of its divisors is an integer number (88664).

2²⁶⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

265989 is a deficient number, since it is larger than the sum of its proper divisors (88667).

265989 is an equidigital number, since it uses as much as digits as its factorization.

265989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88666.

The product of its digits is 38880, while the sum is 39.

The square root of 265989 is about 515.7412141763. The cubic root of 265989 is about 64.3113893915.

The spelling of 265989 in words is "two hundred sixty-five thousand, nine hundred eighty-nine".