265664 has 28 divisors (see below), whose sum is σ = 603504. Its totient is φ = 113664.

The previous prime is 265621. The next prime is 265703. The reversal of 265664 is 466562.

265664 = T₂₇₂ + T₂₇₃ + ... + T₂₇₈.

It is a tau number, because it is divible by the number of its divisors (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152 + ... + 744.

2²⁶⁵⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 265664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (301752).

265664 is an abundant number, since it is smaller than the sum of its proper divisors (337840).

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

265664 is an equidigital number, since it uses as much as digits as its factorization.

265664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612 (or 602 counting only the distinct ones).

The product of its digits is 8640, while the sum is 29.

The square root of 265664 is about 515.4260373710. The cubic root of 265664 is about 64.2851856511.

It can be divided in two parts, 265 and 664, that added together give a palindrome (929).

The spelling of 265664 in words is "two hundred sixty-five thousand, six hundred sixty-four".