123499979 has 2 divisors, whose sum is σ = 123499980. Its totient is φ = 123499978.

The previous prime is 123499967. The next prime is 123499993. The reversal of 123499979 is 979994321.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123499979 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123499979.

It is not a weakly prime, because it can be changed into another prime (123498979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61749989 + 61749990.

It is an arithmetic number, because the mean of its divisors is an integer number (61749990).

Almost surely, 2^123499979 is an apocalyptic number.

123499979 is a deficient number, since it is larger than the sum of its proper divisors (1).

123499979 is an equidigital number, since it uses as much as digits as its factorization.

123499979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1102248, while the sum is 53.

The square root of 123499979 is about 11113.0544406117. The cubic root of 123499979 is about 497.9919180099.

The spelling of 123499979 in words is "one hundred twenty-three million, four hundred ninety-nine thousand, nine hundred seventy-nine".