9966221 has 8 divisors (see below), whose sum is σ = 10464000. Its totient is φ = 9479520.

The previous prime is 9966217. The next prime is 9966223. The reversal of 9966221 is 1226699.

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 9966221 - 2² = 9966217 is a prime.

It is a super-2 number, since 2×9966221² = 198651122041682, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9966223) 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, 896 + ... + 4553.

It is an arithmetic number, because the mean of its divisors is an integer number (1308000).

Almost surely, 2^9966221 is an apocalyptic number.

It is an amenable number.

9966221 is a deficient number, since it is larger than the sum of its proper divisors (497779).

9966221 is a wasteful number, since it uses less digits than its factorization.

9966221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5539.

The product of its digits is 11664, while the sum is 35.

The square root of 9966221 is about 3156.9322133996. The cubic root of 9966221 is about 215.2006131854.

It can be divided in two parts, 99662 and 21, that multiplied together give a palindrome (2092902).

The spelling of 9966221 in words is "nine million, nine hundred sixty-six thousand, two hundred twenty-one".