198305661 has 4 divisors (see below), whose sum is σ = 264407552. Its totient is φ = 132203772.

The previous prime is 198305659. The next prime is 198305671. The reversal of 198305661 is 166503891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 198305661 - 2¹ = 198305659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198305671) 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 3 ways as a sum of consecutive naturals, for example, 33050941 + ... + 33050946.

It is an arithmetic number, because the mean of its divisors is an integer number (66101888).

Almost surely, 2^198305661 is an apocalyptic number.

It is an amenable number.

198305661 is a deficient number, since it is larger than the sum of its proper divisors (66101891).

198305661 is an equidigital number, since it uses as much as digits as its factorization.

198305661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66101890.

The product of its (nonzero) digits is 38880, while the sum is 39.

The square root of 198305661 is about 14082.1042816761. The cubic root of 198305661 is about 583.1474363473.

The spelling of 198305661 in words is "one hundred ninety-eight million, three hundred five thousand, six hundred sixty-one".