5565821 has 2 divisors, whose sum is σ = 5565822. Its totient is φ = 5565820.

The previous prime is 5565809. The next prime is 5565827. The reversal of 5565821 is 1285655.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3463321 + 2102500 = 1861^2 + 1450^2 .

It is a cyclic number.

It is not a de Polignac number, because 5565821 - 2¹⁴ = 5549437 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5565827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2782910 + 2782911.

It is an arithmetic number, because the mean of its divisors is an integer number (2782911).

Almost surely, 2^5565821 is an apocalyptic number.

It is an amenable number.

5565821 is a deficient number, since it is larger than the sum of its proper divisors (1).

5565821 is an equidigital number, since it uses as much as digits as its factorization.

5565821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12000, while the sum is 32.

The square root of 5565821 is about 2359.1992285519. The cubic root of 5565821 is about 177.2187810350.

The spelling of 5565821 in words is "five million, five hundred sixty-five thousand, eight hundred twenty-one".