10661221 has 8 divisors (see below), whose sum is σ = 10895040. Its totient is φ = 10430112.

The previous prime is 10661219. The next prime is 10661237. The reversal of 10661221 is 12216601.

10661221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 10661221 - 2¹ = 10661219 is a prime.

It is a super-2 number, since 2×10661221² = 227323266421682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10661201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8586 + ... + 9748.

It is an arithmetic number, because the mean of its divisors is an integer number (1361880).

Almost surely, 2^10661221 is an apocalyptic number.

It is an amenable number.

10661221 is a deficient number, since it is larger than the sum of its proper divisors (233819).

10661221 is a wasteful number, since it uses less digits than its factorization.

10661221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1355.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 10661221 is about 3265.1525232369. The cubic root of 10661221 is about 220.0910160596.

Adding to 10661221 its reverse (12216601), we get a palindrome (22877822).

The spelling of 10661221 in words is "ten million, six hundred sixty-one thousand, two hundred twenty-one".