7051221 has 24 divisors (see below), whose sum is σ = 10594584. Its totient is φ = 4515840.

The previous prime is 7051211. The next prime is 7051249. The reversal of 7051221 is 1221507.

It can be written as a sum of positive squares in 4 ways, for example, as 1102500 + 5948721 = 1050^2 + 2439^2 .

It is not a de Polignac number, because 7051221 - 2⁵ = 7051189 is a prime.

7051221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 7051194 and 7051203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7051211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35695 + ... + 35891.

It is an arithmetic number, because the mean of its divisors is an integer number (441441).

Almost surely, 2^7051221 is an apocalyptic number.

It is an amenable number.

7051221 is a deficient number, since it is larger than the sum of its proper divisors (3543363).

7051221 is a wasteful number, since it uses less digits than its factorization.

7051221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 7051221 is about 2655.4135271178. The cubic root of 7051221 is about 191.7585669767.

Adding to 7051221 its reverse (1221507), we get a palindrome (8272728).

The spelling of 7051221 in words is "seven million, fifty-one thousand, two hundred twenty-one".