198021766225 has 24 divisors (see below), whose sum is σ = 246711006360. Its totient is φ = 157667051520.

The previous prime is 198021766223. The next prime is 198021766259. The reversal of 198021766225 is 522667120891.

It can be written as a sum of positive squares in 12 ways, for example, as 9492994624 + 188528771601 = 97432^2 + 434199^2 .

It is not a de Polignac number, because 198021766225 - 2¹ = 198021766223 is a prime.

It is not an unprimeable number, because it can be changed into a prime (198021766223) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15890197 + ... + 15902653.

It is an arithmetic number, because the mean of its divisors is an integer number (10279625265).

Almost surely, 2^198021766225 is an apocalyptic number.

It is an amenable number.

198021766225 is a deficient number, since it is larger than the sum of its proper divisors (48689240135).

198021766225 is a wasteful number, since it uses less digits than its factorization.

198021766225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15429 (or 15424 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 49.

The spelling of 198021766225 in words is "one hundred ninety-eight billion, twenty-one million, seven hundred sixty-six thousand, two hundred twenty-five".