7222121 has 2 divisors, whose sum is σ = 7222122. Its totient is φ = 7222120.

The previous prime is 7222099. The next prime is 7222123. The reversal of 7222121 is 1212227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6574096 + 648025 = 2564^2 + 805^2 .

It is an emirp because it is prime and its reverse (1212227) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7222121 is a prime.

Together with 7222123, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7222121.

It is not a weakly prime, because it can be changed into another prime (7222123) 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, 3611060 + 3611061.

It is an arithmetic number, because the mean of its divisors is an integer number (3611061).

Almost surely, 2^7222121 is an apocalyptic number.

It is an amenable number.

7222121 is a deficient number, since it is larger than the sum of its proper divisors (1).

7222121 is an equidigital number, since it uses as much as digits as its factorization.

7222121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 112, while the sum is 17.

The square root of 7222121 is about 2687.4004167597. The cubic root of 7222121 is about 193.2954302099.

Adding to 7222121 its reverse (1212227), we get a palindrome (8434348).

The spelling of 7222121 in words is "seven million, two hundred twenty-two thousand, one hundred twenty-one".