25580 has 12 divisors (see below), whose sum is σ = 53760. Its totient is φ = 10224.

The previous prime is 25579. The next prime is 25583. The reversal of 25580 is 8552.

25580 = 3² + 4² + ... + 42².

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1279 = 25580 / (2 + 5 + 5 + 8 + 0).

It is not an unprimeable number, because it can be changed into a prime (25583) 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, 620 + ... + 659.

It is an arithmetic number, because the mean of its divisors is an integer number (4480).

2²⁵⁵⁸⁰ is an apocalyptic number.

25580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25580 is an abundant number, since it is smaller than the sum of its proper divisors (28180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26880).

25580 is a wasteful number, since it uses less digits than its factorization.

25580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1288 (or 1286 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 25580 is about 159.9374877882. The cubic root of 25580 is about 29.4645749239.

Adding to 25580 its sum of digits (20), we get a square (25600 = 160²).

The spelling of 25580 in words is "twenty-five thousand, five hundred eighty".