4031221 has 2 divisors, whose sum is σ = 4031222. Its totient is φ = 4031220.

The previous prime is 4031219. The next prime is 4031231. The reversal of 4031221 is 1221304.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3944196 + 87025 = 1986^2 + 295^2 .

It is a cyclic number.

It is not a de Polignac number, because 4031221 - 2¹ = 4031219 is a prime.

Together with 4031219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4031201) 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, 2015610 + 2015611.

It is an arithmetic number, because the mean of its divisors is an integer number (2015611).

Almost surely, 2^4031221 is an apocalyptic number.

It is an amenable number.

4031221 is a deficient number, since it is larger than the sum of its proper divisors (1).

4031221 is an equidigital number, since it uses as much as digits as its factorization.

4031221 is an odious number, because the sum of its binary digits is odd.

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

The square root of 4031221 is about 2007.7900786686. The cubic root of 4031221 is about 159.1520373727.

Adding to 4031221 its reverse (1221304), we get a palindrome (5252525).

The spelling of 4031221 in words is "four million, thirty-one thousand, two hundred twenty-one".