123605609 has 2 divisors, whose sum is σ = 123605610. Its totient is φ = 123605608.

The previous prime is 123605597. The next prime is 123605617. The reversal of 123605609 is 906506321.

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., 68890000 + 54715609 = 8300^2 + 7397^2 .

It is a cyclic number.

It is not a de Polignac number, because 123605609 - 2⁸ = 123605353 is a prime.

It is not a weakly prime, because it can be changed into another prime (123605639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61802804 + 61802805.

It is an arithmetic number, because the mean of its divisors is an integer number (61802805).

Almost surely, 2^123605609 is an apocalyptic number.

It is an amenable number.

123605609 is a deficient number, since it is larger than the sum of its proper divisors (1).

123605609 is an equidigital number, since it uses as much as digits as its factorization.

123605609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 123605609 is about 11117.8059436204. The cubic root of 123605609 is about 498.1338556758.

The spelling of 123605609 in words is "one hundred twenty-three million, six hundred five thousand, six hundred nine".