123311999 has 4 divisors (see below), whose sum is σ = 130565664. Its totient is φ = 116058336.

The previous prime is 123311989. The next prime is 123312001. The reversal of 123311999 is 999113321.

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 123311999 - 2⁴ = 123311983 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 (123311939) 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 3 ways as a sum of consecutive naturals, for example, 3626807 + ... + 3626840.

It is an arithmetic number, because the mean of its divisors is an integer number (32641416).

Almost surely, 2^123311999 is an apocalyptic number.

123311999 is a deficient number, since it is larger than the sum of its proper divisors (7253665).

123311999 is an equidigital number, since it uses as much as digits as its factorization.

123311999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7253664.

The product of its digits is 13122, while the sum is 38.

The square root of 123311999 is about 11104.5935990472. The cubic root of 123311999 is about 497.7391242909.

The spelling of 123311999 in words is "one hundred twenty-three million, three hundred eleven thousand, nine hundred ninety-nine".