25999 has 2 divisors, whose sum is σ = 26000. Its totient is φ = 25998.

The previous prime is 25997. The next prime is 26003. The reversal of 25999 is 99952.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25999 - 2¹ = 25997 is a prime.

Together with 25997, it forms a pair of twin primes.

25999 is a modest number, since divided by 999 gives 25 as remainder.

It is a plaindrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12999 + 13000.

It is an arithmetic number, because the mean of its divisors is an integer number (13000).

2²⁵⁹⁹⁹ is an apocalyptic number.

25999 is a deficient number, since it is larger than the sum of its proper divisors (1).

25999 is an equidigital number, since it uses as much as digits as its factorization.

25999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7290, while the sum is 34.

The square root of 25999 is about 161.2420540678. The cubic root of 25999 is about 29.6245808720.

It can be divided in two parts, 25 and 999, that added together give a 10-th power (1024 = 2¹⁰).

The spelling of 25999 in words is "twenty-five thousand, nine hundred ninety-nine".