1265 has 8 divisors (see below), whose sum is σ = 1728. Its totient is φ = 880.

The previous prime is 1259. The next prime is 1277. The reversal of 1265 is 5621.

1265 is nontrivially palindromic in base 4 and base 15.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1265 - 2⁴ = 1249 is a prime.

It is a Duffinian number.

1265 is an undulating number in base 15.

It is a Curzon number.

It is a plaindrome in base 7.

It is a nialpdrome in base 11, base 13 and base 14.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44 + ... + 66.

It is an arithmetic number, because the mean of its divisors is an integer number (216).

2¹²⁶⁵ is an apocalyptic number.

It is an amenable number.

1265 is a deficient number, since it is larger than the sum of its proper divisors (463).

1265 is a wasteful number, since it uses less digits than its factorization.

1265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39.

The product of its digits is 60, while the sum is 14.

The square root of 1265 is about 35.5668384876. The cubic root of 1265 is about 10.8150909291.

Adding to 1265 its reverse (5621), we get a palindrome (6886).

Subtracting 1265 from its reverse (5621), we obtain a square (4356 = 66²).

It can be divided in two parts, 126 and 5, that multiplied together give a triangular number (630 = T₃₅).

The spelling of 1265 in words is "one thousand, two hundred sixty-five".