221236 has 24 divisors (see below), whose sum is σ = 423360. Its totient is φ = 100800.

The previous prime is 221233. The next prime is 221239. The reversal of 221236 is 632122.

221236 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221233) and next prime (221239).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3081 + ... + 3151.

It is an arithmetic number, because the mean of its divisors is an integer number (17640).

2²²¹²³⁶ is an apocalyptic number.

It is an amenable number.

221236 is a deficient number, since it is larger than the sum of its proper divisors (202124).

221236 is a wasteful number, since it uses less digits than its factorization.

221236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135 (or 133 counting only the distinct ones).

The product of its digits is 144, while the sum is 16.

The square root of 221236 is about 470.3573109881. The cubic root of 221236 is about 60.4809493100.

Adding to 221236 its reverse (632122), we get a palindrome (853358).

The spelling of 221236 in words is "two hundred twenty-one thousand, two hundred thirty-six".