198344920921 has 12 divisors (see below), whose sum is σ = 230737595088. Its totient is φ = 170002689192.

The previous prime is 198344920871. The next prime is 198344920993. The reversal of 198344920921 is 129029443891.

It is not a de Polignac number, because 198344920921 - 2⁷ = 198344920793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (198344920621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1301110 + ... + 1445536.

It is an arithmetic number, because the mean of its divisors is an integer number (19228132924).

Almost surely, 2^198344920921 is an apocalyptic number.

It is an amenable number.

198344920921 is a deficient number, since it is larger than the sum of its proper divisors (32392674167).

198344920921 is a wasteful number, since it uses less digits than its factorization.

198344920921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172468 (or 172461 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 52.

The spelling of 198344920921 in words is "one hundred ninety-eight billion, three hundred forty-four million, nine hundred twenty thousand, nine hundred twenty-one".