222221817 has 6 divisors (see below), whose sum is σ = 320987082. Its totient is φ = 148147872.

The previous prime is 222221801. The next prime is 222221819. The reversal of 222221817 is 718122222.

It can be written as a sum of positive squares in only one way, i.e., 219899241 + 2322576 = 14829^2 + 1524^2 .

It is not a de Polignac number, because 222221817 - 2⁴ = 222221801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (222221819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12345648 + ... + 12345665.

It is an arithmetic number, because the mean of its divisors is an integer number (53497847).

Almost surely, 2^222221817 is an apocalyptic number.

It is an amenable number.

222221817 is a deficient number, since it is larger than the sum of its proper divisors (98765265).

222221817 is a wasteful number, since it uses less digits than its factorization.

222221817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24691319 (or 24691316 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 222221817 is about 14907.1062584259. The cubic root of 222221817 is about 605.7064961083.

The spelling of 222221817 in words is "two hundred twenty-two million, two hundred twenty-one thousand, eight hundred seventeen".