25906 has 4 divisors (see below), whose sum is σ = 38862.
Its totient is φ = 12952.
The previous prime is 25903. The next prime is 25913. The reversal of 25906 is 60952.
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., 25281 + 625 = 159^2 + 25^2
It is a super-2 number, since 2×259062 = 1342241672, which contains 22 as substring.
It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.
It is a nialpdrome in base 16.
It is not an unprimeable number, because it can be changed into a prime (25903) 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, 6475 + ... + 6478.
225906 is an apocalyptic number.
25906 is a deficient number, since it is larger than the sum of its proper divisors (12956).
25906 is a wasteful number, since it uses less digits than its factorization.
25906 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 12955.
The product of its (nonzero) digits is 540, while the sum is 22.
The square root of 25906 is about 160.9534094078.
The cubic root of 25906 is about 29.5892156964.
The spelling of 25906 in words is "twenty-five thousand, nine hundred six".