198677779169 has 2 divisors, whose sum is σ = 198677779170. Its totient is φ = 198677779168.

The previous prime is 198677779121. The next prime is 198677779241. The reversal of 198677779169 is 961977776891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146516700625 + 52161078544 = 382775^2 + 228388^2 .

It is a cyclic number.

It is not a de Polignac number, because 198677779169 - 2⁸ = 198677778913 is a prime.

It is a super-2 number, since 2×198677779169² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 198677779169.

It is not a weakly prime, because it can be changed into another prime (198677773169) 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, 99338889584 + 99338889585.

It is an arithmetic number, because the mean of its divisors is an integer number (99338889585).

Almost surely, 2^198677779169 is an apocalyptic number.

It is an amenable number.

198677779169 is a deficient number, since it is larger than the sum of its proper divisors (1).

198677779169 is an equidigital number, since it uses as much as digits as its factorization.

198677779169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 504094752, while the sum is 77.

The spelling of 198677779169 in words is "one hundred ninety-eight billion, six hundred seventy-seven million, seven hundred seventy-nine thousand, one hundred sixty-nine".