2865921 has 4 divisors (see below), whose sum is σ = 3821232. Its totient is φ = 1910612.

The previous prime is 2865917. The next prime is 2865923. The reversal of 2865921 is 1295682.

2865921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2865921 - 2² = 2865917 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (2865923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 477651 + ... + 477656.

It is an arithmetic number, because the mean of its divisors is an integer number (955308).

2^2865921 is an apocalyptic number.

It is an amenable number.

2865921 is a deficient number, since it is larger than the sum of its proper divisors (955311).

2865921 is an equidigital number, since it uses as much as digits as its factorization.

2865921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955310.

The product of its digits is 8640, while the sum is 33.

The square root of 2865921 is about 1692.9031277660. The cubic root of 2865921 is about 142.0435130816.

It can be divided in two parts, 28659 and 21, that added together give a triangular number (28680 = T₂₃₉).

The spelling of 2865921 in words is "two million, eight hundred sixty-five thousand, nine hundred twenty-one".