4013221 has 4 divisors (see below), whose sum is σ = 4027212. Its totient is φ = 3999232.

The previous prime is 4013209. The next prime is 4013227. The reversal of 4013221 is 1223104.

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 1852321 + 2160900 = 1361^2 + 1470^2 .

It is a cyclic number.

It is not a de Polignac number, because 4013221 - 2⁹ = 4012709 is a prime.

It is a super-2 number, since 2×4013221² = 32211885589682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4013227) 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 in 3 ways as a sum of consecutive naturals, for example, 6556 + ... + 7141.

It is an arithmetic number, because the mean of its divisors is an integer number (1006803).

Almost surely, 2^4013221 is an apocalyptic number.

It is an amenable number.

4013221 is a deficient number, since it is larger than the sum of its proper divisors (13991).

4013221 is a wasteful number, since it uses less digits than its factorization.

4013221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13990.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 4013221 is about 2003.3025233349. The cubic root of 4013221 is about 158.9148047736.

Adding to 4013221 its reverse (1223104), we get a palindrome (5236325).

The spelling of 4013221 in words is "four million, thirteen thousand, two hundred twenty-one".