2551 has 2 divisors, whose sum is σ = 2552.
Its totient is φ = 2550.
The previous prime is 2549. The next prime is 2557. The reversal of 2551 is 1552.
Adding to 2551 its product of digits (50), we get a square (2601 = 512).
Subtracting from 2551 its reverse (1552), we obtain a palindrome (999).
It can be divided in two parts, 255 and 1, that added together give a 8-th power (256 = 28).
2551 is nontrivially palindromic in base 6.
It is a weak prime.
It is a cyclic number.
It is not a de Polignac number, because 2551 - 21 = 2549 is a prime.
Together with 2549, it forms a pair of twin primes.
It is the 51-st Hogben number.
It is a plaindrome in base 9.
It is a nialpdrome in base 15.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (2557) by changing a digit.
It is a nontrivial repunit in base 50.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1275 + 1276.
It is an arithmetic number, because the mean of its divisors is an integer number (1276).
22551 is an apocalyptic number.
2551 is a deficient number, since it is larger than the sum of its proper divisors (1).
2551 is an equidigital number, since it uses as much as digits as its factorization.
2551 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 50, while the sum is 13.
The square root of 2551 is about 50.5074251967.
The cubic root of 2551 is about 13.6637577258.
The spelling of 2551 in words is "two thousand, five hundred fifty-one".