198513409 has 4 divisors (see below), whose sum is σ = 198776404. Its totient is φ = 198250416.

The previous prime is 198513283. The next prime is 198513443. The reversal of 198513409 is 904315891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 145733184 + 52780225 = 12072^2 + 7265^2 .

It is a cyclic number.

It is not a de Polignac number, because 198513409 - 2⁷ = 198513281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198513449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 130362 + ... + 131875.

It is an arithmetic number, because the mean of its divisors is an integer number (49694101).

Almost surely, 2^198513409 is an apocalyptic number.

It is an amenable number.

198513409 is a deficient number, since it is larger than the sum of its proper divisors (262995).

198513409 is an equidigital number, since it uses as much as digits as its factorization.

198513409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262994.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 198513409 is about 14089.4786631727. The cubic root of 198513409 is about 583.3510032924.

The spelling of 198513409 in words is "one hundred ninety-eight million, five hundred thirteen thousand, four hundred nine".