198647689 has 2 divisors, whose sum is σ = 198647690. Its totient is φ = 198647688.

The previous prime is 198647663. The next prime is 198647693. The reversal of 198647689 is 986746891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153958464 + 44689225 = 12408^2 + 6685^2 .

It is a cyclic number.

It is not a de Polignac number, because 198647689 - 2¹⁵ = 198614921 is a prime.

It is not a weakly prime, because it can be changed into another prime (198647639) 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, 99323844 + 99323845.

It is an arithmetic number, because the mean of its divisors is an integer number (99323845).

Almost surely, 2^198647689 is an apocalyptic number.

It is an amenable number.

198647689 is a deficient number, since it is larger than the sum of its proper divisors (1).

198647689 is an equidigital number, since it uses as much as digits as its factorization.

198647689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 58.

The square root of 198647689 is about 14094.2431155419. The cubic root of 198647689 is about 583.4825052695.

The spelling of 198647689 in words is "one hundred ninety-eight million, six hundred forty-seven thousand, six hundred eighty-nine".