8221515 has 16 divisors (see below), whose sum is σ = 13197600. Its totient is φ = 4370432.

The previous prime is 8221513. The next prime is 8221537. The reversal of 8221515 is 5151228.

It is a cyclic number.

It is not a de Polignac number, because 8221515 - 2¹ = 8221513 is a prime.

8221515 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (8221513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5131 + ... + 6539.

It is an arithmetic number, because the mean of its divisors is an integer number (824850).

Almost surely, 2^8221515 is an apocalyptic number.

8221515 is a deficient number, since it is larger than the sum of its proper divisors (4976085).

8221515 is a wasteful number, since it uses less digits than its factorization.

8221515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1806.

The product of its digits is 800, while the sum is 24.

The square root of 8221515 is about 2867.3184336589. The cubic root of 8221515 is about 201.8291778730.

The spelling of 8221515 in words is "eight million, two hundred twenty-one thousand, five hundred fifteen".