120198809809 has 9 divisors (see below), whose sum is σ = 130160988273. Its totient is φ = 110948587152.

The previous prime is 120198809749. The next prime is 120198809827. The reversal of 120198809809 is 908908891021.

The square root of 120198809809 is 346697.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 8690900625 + 111507909184 = 93225^2 + 333928^2 .

It is not a de Polignac number, because 120198809809 - 2¹⁹ = 120198285521 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 120198809809.

It is not an unprimeable number, because it can be changed into a prime (120198809839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4493727 + ... + 4520395.

Almost surely, 2^120198809809 is an apocalyptic number.

120198809809 is the 346697-th square number.

120198809809 is the 173349-th centered octagonal number.

It is an amenable number.

120198809809 is a deficient number, since it is larger than the sum of its proper divisors (9962178464).

120198809809 is an frugal number, since it uses more digits than its factorization.

120198809809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53364 (or 26682 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 55.

The spelling of 120198809809 in words is "one hundred twenty billion, one hundred ninety-eight million, eight hundred nine thousand, eight hundred nine".