25578 has 36 divisors (see below), whose sum is σ = 66690. Its totient is φ = 7056.

The previous prime is 25577. The next prime is 25579. The reversal of 25578 is 87552.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (25577) and next prime (25579).

It can be written as a sum of positive squares in only one way, i.e., 21609 + 3969 = 147^2 + 63^2 .

It is a Curzon number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (25577) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 868 + ... + 896.

2²⁵⁵⁷⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25578, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33345).

25578 is an abundant number, since it is smaller than the sum of its proper divisors (41112).

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

25578 is a wasteful number, since it uses less digits than its factorization.

25578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51 (or 41 counting only the distinct ones).

The product of its digits is 2800, while the sum is 27.

The square root of 25578 is about 159.9312352231. The cubic root of 25578 is about 29.4638069973.

It can be divided in two parts, 255 and 78, that added together give a palindrome (333).

The spelling of 25578 in words is "twenty-five thousand, five hundred seventy-eight".