198921967 has 4 divisors (see below), whose sum is σ = 199279656. Its totient is φ = 198564280.

The previous prime is 198921959. The next prime is 198921971. The reversal of 198921967 is 769129891.

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

It is a cyclic number.

It is not a de Polignac number, because 198921967 - 2³ = 198921959 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 (198921977) 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, 178009 + ... + 179122.

It is an arithmetic number, because the mean of its divisors is an integer number (49819914).

Almost surely, 2^198921967 is an apocalyptic number.

198921967 is a deficient number, since it is larger than the sum of its proper divisors (357689).

198921967 is an equidigital number, since it uses as much as digits as its factorization.

198921967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357688.

The product of its digits is 489888, while the sum is 52.

The square root of 198921967 is about 14103.9699021233. The cubic root of 198921967 is about 583.7509248962.

The spelling of 198921967 in words is "one hundred ninety-eight million, nine hundred twenty-one thousand, nine hundred sixty-seven".