9787221 has 12 divisors (see below), whose sum is σ = 14165580. Its totient is φ = 6511680.

The previous prime is 9787177. The next prime is 9787229. The reversal of 9787221 is 1227879.

It can be written as a sum of positive squares in 2 ways, for example, as 239121 + 9548100 = 489^2 + 3090^2 .

It is not a de Polignac number, because 9787221 - 2⁷ = 9787093 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

9787221 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9787229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6135 + ... + 7563.

It is an arithmetic number, because the mean of its divisors is an integer number (1180465).

Almost surely, 2^9787221 is an apocalyptic number.

It is an amenable number.

9787221 is a deficient number, since it is larger than the sum of its proper divisors (4378359).

9787221 is a wasteful number, since it uses less digits than its factorization.

9787221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2196 (or 2193 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 9787221 is about 3128.4534517873. The cubic root of 9787221 is about 213.9044395308.

The spelling of 9787221 in words is "nine million, seven hundred eighty-seven thousand, two hundred twenty-one".