123599 has 4 divisors (see below), whose sum is σ = 141264. Its totient is φ = 105936.

The previous prime is 123593. The next prime is 123601. The reversal of 123599 is 995321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 123599 - 2⁴ = 123583 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8822 + ... + 8835.

It is an arithmetic number, because the mean of its divisors is an integer number (35316).

2¹²³⁵⁹⁹ is an apocalyptic number.

123599 is a deficient number, since it is larger than the sum of its proper divisors (17665).

123599 is an equidigital number, since it uses as much as digits as its factorization.

123599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17664.

The product of its digits is 2430, while the sum is 29.

The square root of 123599 is about 351.5664944218. The cubic root of 123599 is about 49.8124977370.

It can be divided in two parts, 1235 and 99, that multiplied together give a triangular number (122265 = T₄₉₄).

The spelling of 123599 in words is "one hundred twenty-three thousand, five hundred ninety-nine".