10515221 has 4 divisors (see below), whose sum is σ = 10549344. Its totient is φ = 10481100.

The previous prime is 10515217. The next prime is 10515233. The reversal of 10515221 is 12251501.

10515221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 10515221 - 2² = 10515217 is a prime.

It is a super-2 number, since 2×10515221² = 221139745357682, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 10515221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10515251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16595 + ... + 17216.

It is an arithmetic number, because the mean of its divisors is an integer number (2637336).

Almost surely, 2^10515221 is an apocalyptic number.

It is an amenable number.

10515221 is a deficient number, since it is larger than the sum of its proper divisors (34123).

10515221 is an equidigital number, since it uses as much as digits as its factorization.

10515221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34122.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 10515221 is about 3242.7181499477. The cubic root of 10515221 is about 219.0817164799.

Adding to 10515221 its reverse (12251501), we get a palindrome (22766722).

The spelling of 10515221 in words is "ten million, five hundred fifteen thousand, two hundred twenty-one".