7220509 has 4 divisors (see below), whose sum is σ = 7338940. Its totient is φ = 7102080.

The previous prime is 7220497. The next prime is 7220519. The reversal of 7220509 is 9050227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9050227 = 53 ⋅170759.

It can be written as a sum of positive squares in 2 ways, for example, as 1315609 + 5904900 = 1147^2 + 2430^2 .

It is a cyclic number.

It is not a de Polignac number, because 7220509 - 2⁹ = 7219997 is a prime.

It is a Duffinian number.

7220509 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7220519) 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 in 3 ways as a sum of consecutive naturals, for example, 59124 + ... + 59245.

It is an arithmetic number, because the mean of its divisors is an integer number (1834735).

Almost surely, 2^7220509 is an apocalyptic number.

It is an amenable number.

7220509 is a deficient number, since it is larger than the sum of its proper divisors (118431).

7220509 is a wasteful number, since it uses less digits than its factorization.

7220509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118430.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 7220509 is about 2687.1004819322. The cubic root of 7220509 is about 193.2810477582.

The spelling of 7220509 in words is "seven million, two hundred twenty thousand, five hundred nine".