491509354851 has 12 divisors (see below), whose sum is σ = 712786478040. Its totient is φ = 326367432000.

The previous prime is 491509354841. The next prime is 491509354937. The reversal of 491509354851 is 158453905194.

491509354851 is a `hidden beast` number, since 4 + 9 + 1 + 5 + 0 + 93 + 548 + 5 + 1 = 666.

It is not a de Polignac number, because 491509354851 - 2¹⁹ = 491508830563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (491509354841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108786886 + ... + 108791403.

It is an arithmetic number, because the mean of its divisors is an integer number (59398873170).

Almost surely, 2^491509354851 is an apocalyptic number.

491509354851 is a deficient number, since it is larger than the sum of its proper divisors (221277123189).

491509354851 is a wasteful number, since it uses less digits than its factorization.

491509354851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217578546 (or 217578543 counting only the distinct ones).

The product of its (nonzero) digits is 3888000, while the sum is 54.

The spelling of 491509354851 in words is "four hundred ninety-one billion, five hundred nine million, three hundred fifty-four thousand, eight hundred fifty-one".