25658 has 4 divisors (see below), whose sum is σ = 38490. Its totient is φ = 12828.

The previous prime is 25657. The next prime is 25667. The reversal of 25658 is 85652.

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

It can be written as a sum of positive squares in only one way, i.e., 18769 + 6889 = 137^2 + 83^2 .

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

It is not an unprimeable number, because it can be changed into a prime (25657) 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 as a sum of consecutive naturals, namely, 6413 + ... + 6416.

2²⁵⁶⁵⁸ is an apocalyptic number.

25658 is a deficient number, since it is larger than the sum of its proper divisors (12832).

25658 is a wasteful number, since it uses less digits than its factorization.

25658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12831.

The product of its digits is 2400, while the sum is 26.

The square root of 25658 is about 160.1811474550. The cubic root of 25658 is about 29.4944928914.

The spelling of 25658 in words is "twenty-five thousand, six hundred fifty-eight".