491364691 has 2 divisors, whose sum is σ = 491364692. Its totient is φ = 491364690.

The previous prime is 491364607. The next prime is 491364733. The reversal of 491364691 is 196463194.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 491364691 - 2⁷ = 491364563 is a prime.

It is not a weakly prime, because it can be changed into another prime (491365691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245682345 + 245682346.

It is an arithmetic number, because the mean of its divisors is an integer number (245682346).

Almost surely, 2^491364691 is an apocalyptic number.

491364691 is a deficient number, since it is larger than the sum of its proper divisors (1).

491364691 is an equidigital number, since it uses as much as digits as its factorization.

491364691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 43.

The square root of 491364691 is about 22166.7474158930. The cubic root of 491364691 is about 789.1047332995.

The spelling of 491364691 in words is "four hundred ninety-one million, three hundred sixty-four thousand, six hundred ninety-one".