198000123779 has 2 divisors, whose sum is σ = 198000123780. Its totient is φ = 198000123778.

The previous prime is 198000123767. The next prime is 198000123781. The reversal of 198000123779 is 977321000891.

It is a strong prime.

It is an emirp because it is prime and its reverse (977321000891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198000123779 - 2¹² = 198000119683 is a prime.

Together with 198000123781, 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 (198000122779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99000061889 + 99000061890.

It is an arithmetic number, because the mean of its divisors is an integer number (99000061890).

Almost surely, 2^198000123779 is an apocalyptic number.

198000123779 is a deficient number, since it is larger than the sum of its proper divisors (1).

198000123779 is an equidigital number, since it uses as much as digits as its factorization.

198000123779 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 190512, while the sum is 47.

The spelling of 198000123779 in words is "one hundred ninety-eight billion, one hundred twenty-three thousand, seven hundred seventy-nine".