198622657538 has 18 divisors (see below), whose sum is σ = 300063903363. Its totient is φ = 98606367300.

The previous prime is 198622657487. The next prime is 198622657543. The reversal of 198622657538 is 835756226891.

198622657538 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 99311328769 + 99311328769 = 315137^2 + 315137^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=315137.

It is a Duffinian number.

Its product of digits (43545600) is a multiple of the sum of its prime divisors (2240).

It is an unprimeable number.

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, 95170331 + ... + 95172417.

Almost surely, 2^198622657538 is an apocalyptic number.

198622657538 is a deficient number, since it is larger than the sum of its proper divisors (101441245825).

198622657538 is an frugal number, since it uses more digits than its factorization.

198622657538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4478 (or 2240 counting only the distinct ones).

The product of its digits is 43545600, while the sum is 62.

The spelling of 198622657538 in words is "one hundred ninety-eight billion, six hundred twenty-two million, six hundred fifty-seven thousand, five hundred thirty-eight".