221641172 has 12 divisors (see below), whose sum is σ = 410688180. Its totient is φ = 104301696.

The previous prime is 221641163. The next prime is 221641183. The reversal of 221641172 is 271146122.

It can be written as a sum of positive squares in 2 ways, for example, as 142181776 + 79459396 = 11924^2 + 8914^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1629647 + ... + 1629782.

It is an arithmetic number, because the mean of its divisors is an integer number (34224015).

Almost surely, 2^221641172 is an apocalyptic number.

It is an amenable number.

221641172 is a deficient number, since it is larger than the sum of its proper divisors (189047008).

221641172 is a wasteful number, since it uses less digits than its factorization.

221641172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3259450 (or 3259448 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 221641172 is about 14887.6180767778. The cubic root of 221641172 is about 605.1784843244.

Adding to 221641172 its reverse (271146122), we get a palindrome (492787294).

The spelling of 221641172 in words is "two hundred twenty-one million, six hundred forty-one thousand, one hundred seventy-two".