7520221 has 2 divisors, whose sum is σ = 7520222. Its totient is φ = 7520220.

The previous prime is 7520209. The next prime is 7520267. The reversal of 7520221 is 1220257.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7371225 + 148996 = 2715^2 + 386^2 .

It is an emirp because it is prime and its reverse (1220257) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7520221 - 2⁵ = 7520189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7520621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3760110 + 3760111.

It is an arithmetic number, because the mean of its divisors is an integer number (3760111).

Almost surely, 2^7520221 is an apocalyptic number.

It is an amenable number.

7520221 is a deficient number, since it is larger than the sum of its proper divisors (1).

7520221 is an equidigital number, since it uses as much as digits as its factorization.

7520221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 7520221 is about 2742.3021350683. The cubic root of 7520221 is about 195.9191409489.

Adding to 7520221 its reverse (1220257), we get a palindrome (8740478).

The spelling of 7520221 in words is "seven million, five hundred twenty thousand, two hundred twenty-one".