123791609 has 2 divisors, whose sum is σ = 123791610. Its totient is φ = 123791608.

The previous prime is 123791597. The next prime is 123791641. The reversal of 123791609 is 906197321.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 113209600 + 10582009 = 10640^2 + 3253^2 .

It is an emirp because it is prime and its reverse (906197321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123791609 - 2¹² = 123787513 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123791809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61895804 + 61895805.

It is an arithmetic number, because the mean of its divisors is an integer number (61895805).

Almost surely, 2^123791609 is an apocalyptic number.

It is an amenable number.

123791609 is a deficient number, since it is larger than the sum of its proper divisors (1).

123791609 is an equidigital number, since it uses as much as digits as its factorization.

123791609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 123791609 is about 11126.1677589366. The cubic root of 123791609 is about 498.3835920820.

The spelling of 123791609 in words is "one hundred twenty-three million, seven hundred ninety-one thousand, six hundred nine".