2865 has 8 divisors (see below), whose sum is σ = 4608. Its totient is φ = 1520.

The previous prime is 2861. The next prime is 2879. The reversal of 2865 is 5682.

2865 = 3² + 4² + ... + 20².

It is a happy number.

2865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2865 - 2² = 2861 is a prime.

It is a nialpdrome in base 15 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2861) 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, 81 + ... + 110.

It is an arithmetic number, because the mean of its divisors is an integer number (576).

2²⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

2865 is a deficient number, since it is larger than the sum of its proper divisors (1743).

2865 is a wasteful number, since it uses less digits than its factorization.

2865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199.

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

The square root of 2865 is about 53.5256947643. The cubic root of 2865 is about 14.2028295624.

The spelling of 2865 in words is "two thousand, eight hundred sixty-five".