25478 has 4 divisors (see below), whose sum is σ = 38220. Its totient is φ = 12738.

The previous prime is 25471. The next prime is 25523. The reversal of 25478 is 87452.

It is a semiprime because it is the product of two primes.

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

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 25478.

It is not an unprimeable number, because it can be changed into a prime (25471) by changing a digit.

25478 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 as a sum of consecutive naturals, namely, 6368 + ... + 6371.

It is an arithmetic number, because the mean of its divisors is an integer number (9555).

2²⁵⁴⁷⁸ is an apocalyptic number.

25478 is a deficient number, since it is larger than the sum of its proper divisors (12742).

25478 is a wasteful number, since it uses less digits than its factorization.

25478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12741.

The product of its digits is 2240, while the sum is 26.

The square root of 25478 is about 159.6182946908. The cubic root of 25478 is about 29.4253595191.

Subtracting from 25478 its sum of digits (26), we obtain a palindrome (25452).

The spelling of 25478 in words is "twenty-five thousand, four hundred seventy-eight".