491910291822749 has 2 divisors, whose sum is σ = 491910291822750. Its totient is φ = 491910291822748.

The previous prime is 491910291822743. The next prime is 491910291822793. The reversal of 491910291822749 is 947228192019194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 346118118062500 + 145792173760249 = 18604250^2 + 12074443^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491910291822749 is a prime.

It is a super-2 number, since 2×491910291822749² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491910291822743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245955145911374 + 245955145911375.

It is an arithmetic number, because the mean of its divisors is an integer number (245955145911375).

Almost surely, 2^{491910291822749} is an apocalyptic number.

It is an amenable number.

491910291822749 is a deficient number, since it is larger than the sum of its proper divisors (1).

491910291822749 is an equidigital number, since it uses as much as digits as its factorization.

491910291822749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 47029248, while the sum is 68.

The spelling of 491910291822749 in words is "four hundred ninety-one trillion, nine hundred ten billion, two hundred ninety-one million, eight hundred twenty-two thousand, seven hundred forty-nine".