7222221 has 12 divisors (see below), whose sum is σ = 10473372. Its totient is φ = 4795776.

The previous prime is 7222219. The next prime is 7222279. The reversal of 7222221 is 1222227.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1022121 + 6200100 = 1011^2 + 2490^2 .

It is not a de Polignac number, because 7222221 - 2¹ = 7222219 is a prime.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 7222194 and 7222203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7222291) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1045 + ... + 3941.

It is an arithmetic number, because the mean of its divisors is an integer number (872781).

Almost surely, 2^7222221 is an apocalyptic number.

It is an amenable number.

7222221 is a deficient number, since it is larger than the sum of its proper divisors (3251151).

7222221 is a wasteful number, since it uses less digits than its factorization.

7222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3180 (or 3177 counting only the distinct ones).

The product of its digits is 224, while the sum is 18.

The square root of 7222221 is about 2687.4190220358. The cubic root of 7222221 is about 193.2963223511.

Adding to 7222221 its reverse (1222227), we get a palindrome (8444448).

The spelling of 7222221 in words is "seven million, two hundred twenty-two thousand, two hundred twenty-one".