25645 has 8 divisors (see below), whose sum is σ = 32256. Its totient is φ = 19536.

The previous prime is 25643. The next prime is 25657. The reversal of 25645 is 54652.

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

It is a cyclic number.

It is not a de Polignac number, because 25645 - 2¹ = 25643 is a prime.

It is a super-3 number, since 3×25645³ = 50597535633375, which contains 333 as substring.

It is an Ulam number.

It is a Duffinian number.

25645 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4 + ... + 226.

It is an arithmetic number, because the mean of its divisors is an integer number (4032).

2²⁵⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

25645 is a deficient number, since it is larger than the sum of its proper divisors (6611).

25645 is a wasteful number, since it uses less digits than its factorization.

25645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251.

The product of its digits is 1200, while the sum is 22.

The square root of 25645 is about 160.1405632562. The cubic root of 25645 is about 29.4895107781.

The spelling of 25645 in words is "twenty-five thousand, six hundred forty-five".