4220221 has 4 divisors (see below), whose sum is σ = 4233852. Its totient is φ = 4206592.

The previous prime is 4220207. The next prime is 4220239. The reversal of 4220221 is 1220224.

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 756900 + 3463321 = 870^2 + 1861^2 .

It is a cyclic number.

It is not a de Polignac number, because 4220221 - 2⁵ = 4220189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4220521) 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, 6340 + ... + 6973.

It is an arithmetic number, because the mean of its divisors is an integer number (1058463).

Almost surely, 2^4220221 is an apocalyptic number.

It is an amenable number.

4220221 is a deficient number, since it is larger than the sum of its proper divisors (13631).

4220221 is a wasteful number, since it uses less digits than its factorization.

4220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13630.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 4220221 is about 2054.3176482716. The cubic root of 4220221 is about 161.6013798570.

Adding to 4220221 its reverse (1220224), we get a palindrome (5440445).

The spelling of 4220221 in words is "four million, two hundred twenty thousand, two hundred twenty-one".