491566889213 has 2 divisors, whose sum is σ = 491566889214. Its totient is φ = 491566889212.

The previous prime is 491566889153. The next prime is 491566889249. The reversal of 491566889213 is 312988665194.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 456356993764 + 35209895449 = 675542^2 + 187643^2 .

It is a cyclic number.

It is not a de Polignac number, because 491566889213 - 2¹⁴ = 491566872829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491566889713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245783444606 + 245783444607.

It is an arithmetic number, because the mean of its divisors is an integer number (245783444607).

Almost surely, 2^491566889213 is an apocalyptic number.

It is an amenable number.

491566889213 is a deficient number, since it is larger than the sum of its proper divisors (1).

491566889213 is an equidigital number, since it uses as much as digits as its factorization.

491566889213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22394880, while the sum is 62.

The spelling of 491566889213 in words is "four hundred ninety-one billion, five hundred sixty-six million, eight hundred eighty-nine thousand, two hundred thirteen".