123888209 has 2 divisors, whose sum is σ = 123888210. Its totient is φ = 123888208.

The previous prime is 123888199. The next prime is 123888211. The reversal of 123888209 is 902888321.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89113600 + 34774609 = 9440^2 + 5897^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123888209 is a prime.

Together with 123888211, 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 (123888239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61944104 + 61944105.

It is an arithmetic number, because the mean of its divisors is an integer number (61944105).

Almost surely, 2^123888209 is an apocalyptic number.

It is an amenable number.

123888209 is a deficient number, since it is larger than the sum of its proper divisors (1).

123888209 is an equidigital number, since it uses as much as digits as its factorization.

123888209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 55296, while the sum is 41.

The square root of 123888209 is about 11130.5080297352. The cubic root of 123888209 is about 498.5131952053.

The spelling of 123888209 in words is "one hundred twenty-three million, eight hundred eighty-eight thousand, two hundred nine".