198440261 has 4 divisors (see below), whose sum is σ = 198595500. Its totient is φ = 198285024.

The previous prime is 198440239. The next prime is 198440273. The reversal of 198440261 is 162044891.

It is a happy number.

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 177049636 + 21390625 = 13306^2 + 4625^2 .

It is a cyclic number.

It is not a de Polignac number, because 198440261 - 2¹⁴ = 198423877 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 (198440761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75686 + ... + 78263.

It is an arithmetic number, because the mean of its divisors is an integer number (49648875).

Almost surely, 2^198440261 is an apocalyptic number.

It is an amenable number.

198440261 is a deficient number, since it is larger than the sum of its proper divisors (155239).

198440261 is a wasteful number, since it uses less digits than its factorization.

198440261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155238.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 198440261 is about 14086.8825862928. The cubic root of 198440261 is about 583.2793436472.

The spelling of 198440261 in words is "one hundred ninety-eight million, four hundred forty thousand, two hundred sixty-one".