198389729 has 4 divisors (see below), whose sum is σ = 199023876. Its totient is φ = 197755584.

The previous prime is 198389717. The next prime is 198389797. The reversal of 198389729 is 927983891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 927983891 = 2003 ⋅463297.

It can be written as a sum of positive squares in 2 ways, for example, as 3508129 + 194881600 = 1873^2 + 13960^2 .

It is a cyclic number.

It is not a de Polignac number, because 198389729 - 2¹² = 198385633 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (198389129) 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 in 3 ways as a sum of consecutive naturals, for example, 316604 + ... + 317229.

It is an arithmetic number, because the mean of its divisors is an integer number (49755969).

Almost surely, 2^198389729 is an apocalyptic number.

It is an amenable number.

198389729 is a deficient number, since it is larger than the sum of its proper divisors (634147).

198389729 is an equidigital number, since it uses as much as digits as its factorization.

198389729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 634146.

The product of its digits is 1959552, while the sum is 56.

The square root of 198389729 is about 14085.0888886084. The cubic root of 198389729 is about 583.2298295452.

The spelling of 198389729 in words is "one hundred ninety-eight million, three hundred eighty-nine thousand, seven hundred twenty-nine".