123409 has 8 divisors (see below), whose sum is σ = 145152. Its totient is φ = 103440.

The previous prime is 123407. The next prime is 123419. The reversal of 123409 is 904321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 123409 - 2¹ = 123407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 289 + ... + 574.

It is an arithmetic number, because the mean of its divisors is an integer number (18144).

2¹²³⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

123409 is a deficient number, since it is larger than the sum of its proper divisors (21743).

123409 is a wasteful number, since it uses less digits than its factorization.

123409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 887.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 123409 is about 351.2961713426. The cubic root of 123409 is about 49.7869602371.

The spelling of 123409 in words is "one hundred twenty-three thousand, four hundred nine".