123999971 has 2 divisors, whose sum is σ = 123999972. Its totient is φ = 123999970.

The previous prime is 123999929. The next prime is 123999973. The reversal of 123999971 is 179999321.

It is a strong prime.

It is an emirp because it is prime and its reverse (179999321) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123999971 is a prime.

It is a Sophie Germain prime.

Together with 123999973, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123999973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61999985 + 61999986.

It is an arithmetic number, because the mean of its divisors is an integer number (61999986).

Almost surely, 2^123999971 is an apocalyptic number.

123999971 is a deficient number, since it is larger than the sum of its proper divisors (1).

123999971 is an equidigital number, since it uses as much as digits as its factorization.

123999971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 275562, while the sum is 50.

The square root of 123999971 is about 11135.5274235215. The cubic root of 123999971 is about 498.6630563496.

The spelling of 123999971 in words is "one hundred twenty-three million, nine hundred ninety-nine thousand, nine hundred seventy-one".