123398109 has 12 divisors (see below), whose sum is σ = 179140000. Its totient is φ = 81850824.

The previous prime is 123398083. The next prime is 123398113. The reversal of 123398109 is 901893321.

It is not a de Polignac number, because 123398109 - 2⁹ = 123397597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123398129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32659 + ... + 36240.

Almost surely, 2^123398109 is an apocalyptic number.

It is an amenable number.

123398109 is a deficient number, since it is larger than the sum of its proper divisors (55741891).

123398109 is a wasteful number, since it uses less digits than its factorization.

123398109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69104 (or 69101 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 123398109 is about 11108.4701466944. The cubic root of 123398109 is about 497.8549560661.

The spelling of 123398109 in words is "one hundred twenty-three million, three hundred ninety-eight thousand, one hundred nine".