28080020197 has 2 divisors, whose sum is σ = 28080020198. Its totient is φ = 28080020196.

The previous prime is 28080020191. The next prime is 28080020209. The reversal of 28080020197 is 79102008082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22516202916 + 5563817281 = 150054^2 + 74591^2 .

It is a cyclic number.

It is not a de Polignac number, because 28080020197 - 2¹⁹ = 28079495909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28080020191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14040010098 + 14040010099.

It is an arithmetic number, because the mean of its divisors is an integer number (14040010099).

Almost surely, 2^28080020197 is an apocalyptic number.

It is an amenable number.

28080020197 is a deficient number, since it is larger than the sum of its proper divisors (1).

28080020197 is an equidigital number, since it uses as much as digits as its factorization.

28080020197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 37.

The spelling of 28080020197 in words is "twenty-eight billion, eighty million, twenty thousand, one hundred ninety-seven".