263965 has 16 divisors (see below), whose sum is σ = 354816. Its totient is φ = 187200.

The previous prime is 263957. The next prime is 263983. The reversal of 263965 is 569362.

It is not a de Polignac number, because 263965 - 2³ = 263957 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

Its product of digits (9720) is a multiple of the sum of its prime divisors (180).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1950 + ... + 2080.

It is an arithmetic number, because the mean of its divisors is an integer number (22176).

2²⁶³⁹⁶⁵ is an apocalyptic number.

It is an amenable number.

263965 is a deficient number, since it is larger than the sum of its proper divisors (90851).

263965 is a wasteful number, since it uses less digits than its factorization.

263965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180.

The product of its digits is 9720, while the sum is 31.

The square root of 263965 is about 513.7752426889. The cubic root of 263965 is about 64.1478515327.

263965 divided by its sum of digits (31) gives a triangular number (8515 = T₁₃₀).

It can be divided in two parts, 2639 and 65, that added together give a square (2704 = 52²).

The spelling of 263965 in words is "two hundred sixty-three thousand, nine hundred sixty-five".