4865821 has 2 divisors, whose sum is σ = 4865822. Its totient is φ = 4865820.

The previous prime is 4865803. The next prime is 4865827. The reversal of 4865821 is 1285684.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2524921 + 2340900 = 1589^2 + 1530^2 .

It is a cyclic number.

It is not a de Polignac number, because 4865821 - 2¹⁷ = 4734749 is a prime.

4865821 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4865827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2432910 + 2432911.

It is an arithmetic number, because the mean of its divisors is an integer number (2432911).

Almost surely, 2^4865821 is an apocalyptic number.

It is an amenable number.

4865821 is a deficient number, since it is larger than the sum of its proper divisors (1).

4865821 is an equidigital number, since it uses as much as digits as its factorization.

4865821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15360, while the sum is 34.

The square root of 4865821 is about 2205.8606030300. The cubic root of 4865821 is about 169.4540850159.

The spelling of 4865821 in words is "four million, eight hundred sixty-five thousand, eight hundred twenty-one".