12785 has 4 divisors (see below), whose sum is σ = 15348. Its totient is φ = 10224.

The previous prime is 12781. The next prime is 12791. The reversal of 12785 is 58721.

12785 = T₆₉ + T₇₀ + ... + T₇₃.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58721 = 13 ⋅4517.

It can be written as a sum of positive squares in 2 ways, for example, as 5041 + 7744 = 71^2 + 88^2 .

It is a cyclic number.

It is not a de Polignac number, because 12785 - 2² = 12781 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12785.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1274 + ... + 1283.

It is an arithmetic number, because the mean of its divisors is an integer number (3837).

2¹²⁷⁸⁵ is an apocalyptic number.

It is an amenable number.

12785 is a deficient number, since it is larger than the sum of its proper divisors (2563).

12785 is an equidigital number, since it uses as much as digits as its factorization.

12785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2562.

The product of its digits is 560, while the sum is 23.

The square root of 12785 is about 113.0707742965. The cubic root of 12785 is about 23.3830007786.

It can be divided in two parts, 127 and 85, that added together give a palindrome (212).

The spelling of 12785 in words is "twelve thousand, seven hundred eighty-five".