7221439 has 2 divisors, whose sum is σ = 7221440. Its totient is φ = 7221438.

The previous prime is 7221391. The next prime is 7221449. The reversal of 7221439 is 9341227.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7221439 - 2¹¹ = 7219391 is a prime.

It is a Chen prime.

7221439 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7221449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3610719 + 3610720.

It is an arithmetic number, because the mean of its divisors is an integer number (3610720).

Almost surely, 2^7221439 is an apocalyptic number.

7221439 is a deficient number, since it is larger than the sum of its proper divisors (1).

7221439 is an equidigital number, since it uses as much as digits as its factorization.

7221439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 28.

The square root of 7221439 is about 2687.2735253413. The cubic root of 7221439 is about 193.2893455877.

The spelling of 7221439 in words is "seven million, two hundred twenty-one thousand, four hundred thirty-nine".