7221515 has 32 divisors (see below), whose sum is σ = 10730880. Its totient is φ = 4552704.

The previous prime is 7221509. The next prime is 7221523. The reversal of 7221515 is 5151227.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 7221515 - 2⁴ = 7221499 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31421 + ... + 31649.

It is an arithmetic number, because the mean of its divisors is an integer number (335340).

Almost surely, 2^7221515 is an apocalyptic number.

7221515 is a deficient number, since it is larger than the sum of its proper divisors (3509365).

7221515 is a wasteful number, since it uses less digits than its factorization.

7221515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311.

The product of its digits is 700, while the sum is 23.

The square root of 7221515 is about 2687.2876660306. The cubic root of 7221515 is about 193.2900236584.

The spelling of 7221515 in words is "seven million, two hundred twenty-one thousand, five hundred fifteen".