2549 has 2 divisors, whose sum is σ = 2550.
Its totient is φ = 2548.
The previous prime is 2543. The next prime is 2551. The reversal of 2549 is 9452.
2549 is nontrivially palindromic in base 7.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 2500 + 49 = 50^2 + 7^2
It is a cyclic number.
It is not a de Polignac number, because 2549 - 28 = 2293 is a prime.
It is a Sophie Germain prime.
Together with 2551, it forms a pair of twin primes.
It is a Chen prime.
It is an alternating number because its digits alternate between even and odd.
It is a Curzon number.
It is a self number, because there is not a number n which added to its sum of digits gives 2549.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (2543) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1274 + 1275.
It is an arithmetic number, because the mean of its divisors is an integer number (1275).
22549 is an apocalyptic number.
It is an amenable number.
2549 is a deficient number, since it is larger than the sum of its proper divisors (1).
2549 is an equidigital number, since it uses as much as digits as its factorization.
2549 is an evil number, because the sum of its binary digits is even.
The product of its digits is 360, while the sum is 20.
The square root of 2549 is about 50.4876222455.
The cubic root of 2549 is about 13.6601859683.
Subtracting 2549 from its reverse (9452), we obtain a triangular number (6903 = T117).
It can be divided in two parts, 25 and 49, that multiplied together give a triangular number (1225 = T49).
The spelling of 2549 in words is "two thousand, five hundred forty-nine".