7231221 has 16 divisors (see below), whose sum is σ = 10769920. Its totient is φ = 4795200.

The previous prime is 7231219. The next prime is 7231247. The reversal of 7231221 is 1221327.

It is not a de Polignac number, because 7231221 - 2¹ = 7231219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7231194 and 7231203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7231201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5421 + ... + 6621.

It is an arithmetic number, because the mean of its divisors is an integer number (673120).

Almost surely, 2^7231221 is an apocalyptic number.

It is an amenable number.

7231221 is a deficient number, since it is larger than the sum of its proper divisors (3538699).

7231221 is a wasteful number, since it uses less digits than its factorization.

7231221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1433 (or 1427 counting only the distinct ones).

The product of its digits is 168, while the sum is 18.

The square root of 7231221 is about 2689.0929697576. The cubic root of 7231221 is about 193.3765813540.

Adding to 7231221 its reverse (1221327), we get a palindrome (8452548).

The spelling of 7231221 in words is "seven million, two hundred thirty-one thousand, two hundred twenty-one".