198961609 has 16 divisors (see below), whose sum is σ = 253123200. Its totient is φ = 155032080.

The previous prime is 198961603. The next prime is 198961613. The reversal of 198961609 is 906169891.

It is not a de Polignac number, because 198961609 - 2³ = 198961601 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is not an unprimeable number, because it can be changed into a prime (198961601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22594 + ... + 30139.

It is an arithmetic number, because the mean of its divisors is an integer number (15820200).

Almost surely, 2^198961609 is an apocalyptic number.

It is an amenable number.

198961609 is a deficient number, since it is larger than the sum of its proper divisors (54161591).

198961609 is an equidigital number, since it uses as much as digits as its factorization.

198961609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52765 (or 52751 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 49.

The square root of 198961609 is about 14105.3751811145. The cubic root of 198961609 is about 583.7896997610.

The spelling of 198961609 in words is "one hundred ninety-eight million, nine hundred sixty-one thousand, six hundred nine".