10665221 has 4 divisors (see below), whose sum is σ = 12188832. Its totient is φ = 9141612.

The previous prime is 10665199. The next prime is 10665229. The reversal of 10665221 is 12256601.

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 10665221 - 2⁶ = 10665157 is a prime.

It is a super-2 number, since 2×10665221² = 227493877957682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10665229) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 761795 + ... + 761808.

It is an arithmetic number, because the mean of its divisors is an integer number (3047208).

Almost surely, 2^10665221 is an apocalyptic number.

It is an amenable number.

10665221 is a deficient number, since it is larger than the sum of its proper divisors (1523611).

10665221 is an equidigital number, since it uses as much as digits as its factorization.

10665221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1523610.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 10665221 is about 3265.7649946069. The cubic root of 10665221 is about 220.1185380475.

The spelling of 10665221 in words is "ten million, six hundred sixty-five thousand, two hundred twenty-one".