2813 has 4 divisors (see below), whose sum is σ = 2940.
Its totient is φ = 2688.
The previous prime is 2803. The next prime is 2819. The reversal of 2813 is 3182.
Added to its reverse (3182) it gives a triangular number (5995 = T109).
2813 = 372 + 382.
It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.
It can be written as a sum of positive squares in 2 ways, for example, as 1369 + 1444 = 37^2 + 38^2
It is a cyclic number.
It is not a de Polignac number, because 2813 - 24 = 2797 is a prime.
It is a Duffinian number.
It is a plaindrome in base 7.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (2819) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20 + ... + 77.
It is an arithmetic number, because the mean of its divisors is an integer number (735).
2813 is the 38-th centered square number.
It is an amenable number.
2813 is a deficient number, since it is larger than the sum of its proper divisors (127).
2813 is an equidigital number, since it uses as much as digits as its factorization.
2813 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 126.
The product of its digits is 48, while the sum is 14.
The square root of 2813 is about 53.0377224247.
The cubic root of 2813 is about 14.1163768601.
Adding to 2813 its reverse (3182), we get a palindrome (5995).
The spelling of 2813 in words is "two thousand, eight hundred thirteen".