198264568321 has 2 divisors, whose sum is σ = 198264568322. Its totient is φ = 198264568320.

The previous prime is 198264568319. The next prime is 198264568387. The reversal of 198264568321 is 123865462891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 165661210225 + 32603358096 = 407015^2 + 180564^2 .

It is a cyclic number.

It is not a de Polignac number, because 198264568321 - 2¹ = 198264568319 is a prime.

Together with 198264568319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (198264568921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99132284160 + 99132284161.

It is an arithmetic number, because the mean of its divisors is an integer number (99132284161).

Almost surely, 2^198264568321 is an apocalyptic number.

It is an amenable number.

198264568321 is a deficient number, since it is larger than the sum of its proper divisors (1).

198264568321 is an equidigital number, since it uses as much as digits as its factorization.

198264568321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4976640, while the sum is 55.

The spelling of 198264568321 in words is "one hundred ninety-eight billion, two hundred sixty-four million, five hundred sixty-eight thousand, three hundred twenty-one".