198274021 has 4 divisors (see below), whose sum is σ = 216298944. Its totient is φ = 180249100.

The previous prime is 198274019. The next prime is 198274033. The reversal of 198274021 is 120472891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 198274021 - 2¹ = 198274019 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 (198274001) 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, 9012445 + ... + 9012466.

It is an arithmetic number, because the mean of its divisors is an integer number (54074736).

Almost surely, 2^198274021 is an apocalyptic number.

198274021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

198274021 is a deficient number, since it is larger than the sum of its proper divisors (18024923).

198274021 is a wasteful number, since it uses less digits than its factorization.

198274021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18024922.

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 198274021 is about 14080.9808252124. The cubic root of 198274021 is about 583.1164206480.

The spelling of 198274021 in words is "one hundred ninety-eight million, two hundred seventy-four thousand, twenty-one".