991749263 has 2 divisors, whose sum is σ = 991749264. Its totient is φ = 991749262.

The previous prime is 991749191. The next prime is 991749301. The reversal of 991749263 is 362947199.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991749263 - 2¹⁶ = 991683727 is a prime.

It is a super-2 number, since 2×991749263² = 1967133201322086338, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (991719263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495874631 + 495874632.

It is an arithmetic number, because the mean of its divisors is an integer number (495874632).

Almost surely, 2^991749263 is an apocalyptic number.

991749263 is a deficient number, since it is larger than the sum of its proper divisors (1).

991749263 is an equidigital number, since it uses as much as digits as its factorization.

991749263 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 734832, while the sum is 50.

The square root of 991749263 is about 31492.0507906360. The cubic root of 991749263 is about 997.2421556195.

The spelling of 991749263 in words is "nine hundred ninety-one million, seven hundred forty-nine thousand, two hundred sixty-three".