7220557 has 2 divisors, whose sum is σ = 7220558. Its totient is φ = 7220556.

The previous prime is 7220531. The next prime is 7220569. The reversal of 7220557 is 7550227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6456681 + 763876 = 2541^2 + 874^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7220557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7224557) 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, 3610278 + 3610279.

It is an arithmetic number, because the mean of its divisors is an integer number (3610279).

Almost surely, 2^7220557 is an apocalyptic number.

It is an amenable number.

7220557 is a deficient number, since it is larger than the sum of its proper divisors (1).

7220557 is an equidigital number, since it uses as much as digits as its factorization.

7220557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4900, while the sum is 28.

The square root of 7220557 is about 2687.1094134776. The cubic root of 7220557 is about 193.2814760507.

It can be divided in two parts, 7220 and 557, that added together give a palindrome (7777).

The spelling of 7220557 in words is "seven million, two hundred twenty thousand, five hundred fifty-seven".