2864821 has 4 divisors (see below), whose sum is σ = 2897100. Its totient is φ = 2832544.

The previous prime is 2864761. The next prime is 2864831. The reversal of 2864821 is 1284682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 703921 + 2160900 = 839^2 + 1470^2 .

It is a cyclic number.

It is not a de Polignac number, because 2864821 - 2¹⁷ = 2733749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2864831) 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, 16006 + ... + 16183.

It is an arithmetic number, because the mean of its divisors is an integer number (724275).

2^2864821 is an apocalyptic number.

It is an amenable number.

2864821 is a deficient number, since it is larger than the sum of its proper divisors (32279).

2864821 is an equidigital number, since it uses as much as digits as its factorization.

2864821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32278.

The product of its digits is 6144, while the sum is 31.

The square root of 2864821 is about 1692.5782108960. The cubic root of 2864821 is about 142.0253376726.

The spelling of 2864821 in words is "two million, eight hundred sixty-four thousand, eight hundred twenty-one".