2099221 has 2 divisors, whose sum is σ = 2099222. Its totient is φ = 2099220.

The previous prime is 2099219. The next prime is 2099249. The reversal of 2099221 is 1229902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1234321 + 864900 = 1111^2 + 930^2 .

It is a cyclic number.

It is not a de Polignac number, because 2099221 - 2¹ = 2099219 is a prime.

Together with 2099219, it forms a pair of twin primes.

It is a d-powerful number, because it can be written as 2 + 0 + 9 + 9 + 2¹¹ + 2²¹ + 1 .

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2099021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1049610 + 1049611.

It is an arithmetic number, because the mean of its divisors is an integer number (1049611).

2^2099221 is an apocalyptic number.

It is an amenable number.

2099221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2099221 is an equidigital number, since it uses as much as digits as its factorization.

2099221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 2099221 is about 1448.8688691528. The cubic root of 2099221 is about 128.0420800774.

The spelling of 2099221 in words is "two million, ninety-nine thousand, two hundred twenty-one".