123221009 has 2 divisors, whose sum is σ = 123221010. Its totient is φ = 123221008.

The previous prime is 123220967. The next prime is 123221011. The reversal of 123221009 is 900122321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 102718225 + 20502784 = 10135^2 + 4528^2 .

It is a cyclic number.

It is not a de Polignac number, because 123221009 - 2²⁰ = 122172433 is a prime.

Together with 123221011, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123221069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61610504 + 61610505.

It is an arithmetic number, because the mean of its divisors is an integer number (61610505).

Almost surely, 2^123221009 is an apocalyptic number.

It is an amenable number.

123221009 is a deficient number, since it is larger than the sum of its proper divisors (1).

123221009 is an equidigital number, since it uses as much as digits as its factorization.

123221009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 123221009 is about 11100.4958898240. The cubic root of 123221009 is about 497.6166695223.

It can be divided in two parts, 12322 and 1009, that added together give a palindrome (13331).

The spelling of 123221009 in words is "one hundred twenty-three million, two hundred twenty-one thousand, nine".