198645491 has 8 divisors (see below), whose sum is σ = 218809344. Its totient is φ = 178832520.

The previous prime is 198645481. The next prime is 198645511. The reversal of 198645491 is 194546891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198645491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198645481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86531 + ... + 88796.

It is an arithmetic number, because the mean of its divisors is an integer number (27351168).

Almost surely, 2^198645491 is an apocalyptic number.

198645491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

198645491 is a deficient number, since it is larger than the sum of its proper divisors (20163853).

198645491 is a wasteful number, since it uses less digits than its factorization.

198645491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175441.

The product of its digits is 311040, while the sum is 47.

The square root of 198645491 is about 14094.1651402274. The cubic root of 198645491 is about 583.4803532195.

The spelling of 198645491 in words is "one hundred ninety-eight million, six hundred forty-five thousand, four hundred ninety-one".