25851 has 8 divisors (see below), whose sum is σ = 39424.
Its totient is φ = 14760.
The previous prime is 25849. The next prime is 25867. The reversal of 25851 is 15852.
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 25851 - 21 = 25849 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 1231 = 25851 / (2 + 5 + 8 + 5 + 1).
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 25851.
It is not an unprimeable number, because it can be changed into a prime (25801) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 595 + ... + 636.
It is an arithmetic number, because the mean of its divisors is an integer number (4928).
225851 is an apocalyptic number.
25851 is a gapful number since it is divisible by the number (21) formed by its first and last digit.
25851 is a deficient number, since it is larger than the sum of its proper divisors (13573).
25851 is a wasteful number, since it uses less digits than its factorization.
25851 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1241.
The product of its digits is 400, while the sum is 21.
The square root of 25851 is about 160.7824617301.
The cubic root of 25851 is about 29.5682609637.
Subtracting from 25851 its reverse (15852), we obtain a palindrome (9999).
The spelling of 25851 in words is "twenty-five thousand, eight hundred fifty-one".