491039857091 has 8 divisors (see below), whose sum is σ = 561277380864. Its totient is φ = 420824576520.

The previous prime is 491039857013. The next prime is 491039857129. The reversal of 491039857091 is 190758930194.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491039857091 is a prime.

It is a super-2 number, since 2×491039857091² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491039857691) 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 in 7 ways as a sum of consecutive naturals, for example, 5513465 + ... + 5601818.

It is an arithmetic number, because the mean of its divisors is an integer number (70159672608).

Almost surely, 2^491039857091 is an apocalyptic number.

491039857091 is a deficient number, since it is larger than the sum of its proper divisors (70237523773).

491039857091 is a wasteful number, since it uses less digits than its factorization.

491039857091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11121601.

The product of its (nonzero) digits is 2449440, while the sum is 56.

The spelling of 491039857091 in words is "four hundred ninety-one billion, thirty-nine million, eight hundred fifty-seven thousand, ninety-one".