198197090588657 has 2 divisors, whose sum is σ = 198197090588658. Its totient is φ = 198197090588656.

The previous prime is 198197090588621. The next prime is 198197090588699. The reversal of 198197090588657 is 756885090791891.

198197090588657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197043236509681 + 1153854078976 = 14037209^2 + 1074176^2 .

It is a cyclic number.

It is not a de Polignac number, because 198197090588657 - 2¹⁸ = 198197090326513 is a prime.

It is not a weakly prime, because it can be changed into another prime (198197090588617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99098545294328 + 99098545294329.

It is an arithmetic number, because the mean of its divisors is an integer number (99098545294329).

Almost surely, 2^{198197090588657} is an apocalyptic number.

It is an amenable number.

198197090588657 is a deficient number, since it is larger than the sum of its proper divisors (1).

198197090588657 is an equidigital number, since it uses as much as digits as its factorization.

198197090588657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2743372800, while the sum is 83.

The spelling of 198197090588657 in words is "one hundred ninety-eight trillion, one hundred ninety-seven billion, ninety million, five hundred eighty-eight thousand, six hundred fifty-seven".