123965999 has 4 divisors (see below), whose sum is σ = 124003440. Its totient is φ = 123928560.

The previous prime is 123965953. The next prime is 123966047. The reversal of 123965999 is 999569321.

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 123965999 - 2²⁰ = 122917423 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 123965999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123965909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13214 + ... + 20555.

It is an arithmetic number, because the mean of its divisors is an integer number (31000860).

Almost surely, 2^123965999 is an apocalyptic number.

123965999 is a deficient number, since it is larger than the sum of its proper divisors (37441).

123965999 is an equidigital number, since it uses as much as digits as its factorization.

123965999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37440.

The product of its digits is 1180980, while the sum is 53.

The square root of 123965999 is about 11134.0019310219. The cubic root of 123965999 is about 498.6175129824.

The spelling of 123965999 in words is "one hundred twenty-three million, nine hundred sixty-five thousand, nine hundred ninety-nine".