123245209 has 2 divisors, whose sum is σ = 123245210. Its totient is φ = 123245208.

The previous prime is 123245207. The next prime is 123245249. The reversal of 123245209 is 902542321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 116035984 + 7209225 = 10772^2 + 2685^2 .

It is a cyclic number.

It is not a de Polignac number, because 123245209 - 2¹ = 123245207 is a prime.

Together with 123245207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (123245203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61622604 + 61622605.

It is an arithmetic number, because the mean of its divisors is an integer number (61622605).

Almost surely, 2^123245209 is an apocalyptic number.

It is an amenable number.

123245209 is a deficient number, since it is larger than the sum of its proper divisors (1).

123245209 is an equidigital number, since it uses as much as digits as its factorization.

123245209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 123245209 is about 11101.5858777023. The cubic root of 123245209 is about 497.6492438785.

The spelling of 123245209 in words is "one hundred twenty-three million, two hundred forty-five thousand, two hundred nine".