2856 has 32 divisors (see below), whose sum is σ = 8640. Its totient is φ = 768.

The previous prime is 2851. The next prime is 2857. The reversal of 2856 is 6582.

2856 = T₂₅ + T₂₆ + ... + T₃₁.

2856 = 4² + 5² + ... + 20².

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (2851) by changing a digit.

2856 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 160 + ... + 176.

It is an arithmetic number, because the mean of its divisors is an integer number (270).

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4320).

2856 is an abundant number, since it is smaller than the sum of its proper divisors (5784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2856 is a wasteful number, since it uses less digits than its factorization.

2856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33 (or 29 counting only the distinct ones).

The product of its digits is 480, while the sum is 21.

The square root of 2856 is about 53.4415568635. The cubic root of 2856 is about 14.1879418895.

2856 divided by its sum of digits (21) gives a triangular number (136 = T₁₆).

It can be divided in two parts, 2 and 856, that added together give a palindrome (858).

The spelling of 2856 in words is "two thousand, eight hundred fifty-six".