491210197 has 2 divisors, whose sum is σ = 491210198. Its totient is φ = 491210196.

The previous prime is 491210177. The next prime is 491210243. The reversal of 491210197 is 791012194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 487791396 + 3418801 = 22086^2 + 1849^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491210197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491210177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245605098 + 245605099.

It is an arithmetic number, because the mean of its divisors is an integer number (245605099).

Almost surely, 2^491210197 is an apocalyptic number.

It is an amenable number.

491210197 is a deficient number, since it is larger than the sum of its proper divisors (1).

491210197 is an equidigital number, since it uses as much as digits as its factorization.

491210197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 34.

The square root of 491210197 is about 22163.2623275546. The cubic root of 491210197 is about 789.0220216679.

The spelling of 491210197 in words is "four hundred ninety-one million, two hundred ten thousand, one hundred ninety-seven".