491778194987508 has 96 divisors (see below), whose sum is σ = 1348119875934720. Its totient is φ = 137557415879040.

The previous prime is 491778194987507. The next prime is 491778194987557. The reversal of 491778194987508 is 805789491877194.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491778194987507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78505783 + ... + 84538241.

It is an arithmetic number, because the mean of its divisors is an integer number (14042915374320).

Almost surely, 2^{491778194987508} is an apocalyptic number.

It is an amenable number.

491778194987508 is an abundant number, since it is smaller than the sum of its proper divisors (856341680947212).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491778194987508 is a wasteful number, since it uses less digits than its factorization.

491778194987508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6079997 (or 6079995 counting only the distinct ones).

The product of its (nonzero) digits is 10241925120, while the sum is 87.

The spelling of 491778194987508 in words is "four hundred ninety-one trillion, seven hundred seventy-eight billion, one hundred ninety-four million, nine hundred eighty-seven thousand, five hundred eight".