25709 has 4 divisors (see below), whose sum is σ = 26304. Its totient is φ = 25116.

The previous prime is 25703. The next prime is 25717. The reversal of 25709 is 90752.

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 a cyclic number.

It is not a de Polignac number, because 25709 - 2⁴ = 25693 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25703) 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, 227 + ... + 320.

It is an arithmetic number, because the mean of its divisors is an integer number (6576).

2²⁵⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

25709 is a deficient number, since it is larger than the sum of its proper divisors (595).

25709 is an equidigital number, since it uses as much as digits as its factorization.

25709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594.

The product of its (nonzero) digits is 630, while the sum is 23.

The square root of 25709 is about 160.3402631905. The cubic root of 25709 is about 29.5140218700.

The spelling of 25709 in words is "twenty-five thousand, seven hundred nine".