491851547577 has 12 divisors (see below), whose sum is σ = 765102407524. Its totient is φ = 302677875360.

The previous prime is 491851547563. The next prime is 491851547581. The reversal of 491851547577 is 775745158194.

491851547577 is a `hidden beast` number, since 4 + 9 + 1 + 8 + 5 + 1 + 54 + 7 + 577 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 115587080361 + 376264467216 = 339981^2 + 613404^2 .

It is not a de Polignac number, because 491851547577 - 2⁸ = 491851547321 is a prime.

It is not an unprimeable number, because it can be changed into a prime (491851547527) 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 11 ways as a sum of consecutive naturals, for example, 2101929574 + ... + 2101929807.

Almost surely, 2^491851547577 is an apocalyptic number.

It is an amenable number.

491851547577 is a deficient number, since it is larger than the sum of its proper divisors (273250859947).

491851547577 is a wasteful number, since it uses less digits than its factorization.

491851547577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4203859400 (or 4203859397 counting only the distinct ones).

The product of its digits is 49392000, while the sum is 63.

The spelling of 491851547577 in words is "four hundred ninety-one billion, eight hundred fifty-one million, five hundred forty-seven thousand, five hundred seventy-seven".