1223642221 has 4 divisors (see below), whose sum is σ = 1237391100. Its totient is φ = 1209893344.

The previous prime is 1223642183. The next prime is 1223642243. The reversal of 1223642221 is 1222463221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 211702500 + 1011939721 = 14550^2 + 31811^2 .

It is a cyclic number.

It is not a de Polignac number, because 1223642221 - 2⁹ = 1223641709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223642621) by changing a digit.

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, 6874306 + ... + 6874483.

It is an arithmetic number, because the mean of its divisors is an integer number (309347775).

Almost surely, 2^1223642221 is an apocalyptic number.

It is an amenable number.

1223642221 is a deficient number, since it is larger than the sum of its proper divisors (13748879).

1223642221 is an equidigital number, since it uses as much as digits as its factorization.

1223642221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13748878.

The product of its digits is 2304, while the sum is 25.

The square root of 1223642221 is about 34980.5977793405. The cubic root of 1223642221 is about 1069.5920129130.

The spelling of 1223642221 in words is "one billion, two hundred twenty-three million, six hundred forty-two thousand, two hundred twenty-one".