198639673 has 2 divisors, whose sum is σ = 198639674. Its totient is φ = 198639672.

The previous prime is 198639659. The next prime is 198639691. The reversal of 198639673 is 376936891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 188980009 + 9659664 = 13747^2 + 3108^2 .

It is a cyclic number.

It is not a de Polignac number, because 198639673 - 2⁵ = 198639641 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198639673.

It is not a weakly prime, because it can be changed into another prime (198639073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99319836 + 99319837.

It is an arithmetic number, because the mean of its divisors is an integer number (99319837).

Almost surely, 2^198639673 is an apocalyptic number.

It is an amenable number.

198639673 is a deficient number, since it is larger than the sum of its proper divisors (1).

198639673 is an equidigital number, since it uses as much as digits as its factorization.

198639673 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1469664, while the sum is 52.

The square root of 198639673 is about 14093.9587412480. The cubic root of 198639673 is about 583.4746567703.

The spelling of 198639673 in words is "one hundred ninety-eight million, six hundred thirty-nine thousand, six hundred seventy-three".