198335649082561 has 3 divisors (see below), whose sum is σ = 198335663165731. Its totient is φ = 198335634999392.

The previous prime is 198335649082537. The next prime is 198335649082567. The reversal of 198335649082561 is 165280946533891.

The square root of 198335649082561 is 14083169.

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

198335649082561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 154157825792961 + 44177823289600 = 12416031^2 + 6646640^2 .

It is not a de Polignac number, because 198335649082561 - 2⁷ = 198335649082433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198335649082567) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 7041585 + ... + 21124753.

Almost surely, 2^{198335649082561} is an apocalyptic number.

198335649082561 is the 14083169-th square number.

198335649082561 is the 7041585-th centered octagonal number.

It is an amenable number.

198335649082561 is a deficient number, since it is larger than the sum of its proper divisors (14083170).

198335649082561 is an frugal number, since it uses more digits than its factorization.

198335649082561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28166338 (or 14083169 counting only the distinct ones).

The product of its (nonzero) digits is 335923200, while the sum is 70.

The spelling of 198335649082561 in words is "one hundred ninety-eight trillion, three hundred thirty-five billion, six hundred forty-nine million, eighty-two thousand, five hundred sixty-one".