4042242221 has 2 divisors, whose sum is σ = 4042242222. Its totient is φ = 4042242220.

The previous prime is 4042242173. The next prime is 4042242223. The reversal of 4042242221 is 1222422404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2851026025 + 1191216196 = 53395^2 + 34514^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4042242221 is a prime.

Together with 4042242223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4042242223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2021121110 + 2021121111.

It is an arithmetic number, because the mean of its divisors is an integer number (2021121111).

Almost surely, 2^4042242221 is an apocalyptic number.

It is an amenable number.

4042242221 is a deficient number, since it is larger than the sum of its proper divisors (1).

4042242221 is an equidigital number, since it uses as much as digits as its factorization.

4042242221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2048, while the sum is 23.

The square root of 4042242221 is about 63578.6302227407. The cubic root of 4042242221 is about 1592.9694414709.

Adding to 4042242221 its reverse (1222422404), we get a palindrome (5264664625).

The spelling of 4042242221 in words is "four billion, forty-two million, two hundred forty-two thousand, two hundred twenty-one".