831781081656 has 128 divisors (see below), whose sum is σ = 2731629312000. Its totient is φ = 229456838016.

The previous prime is 831781081631. The next prime is 831781081699. The reversal of 831781081656 is 656180187138.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9440976 + ... + 9528671.

It is an arithmetic number, because the mean of its divisors is an integer number (21340854000).

Almost surely, 2^831781081656 is an apocalyptic number.

It is an amenable number.

831781081656 is an abundant number, since it is smaller than the sum of its proper divisors (1899848230344).

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

831781081656 is a wasteful number, since it uses less digits than its factorization.

831781081656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18969698 (or 18969688 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 54.

The spelling of 831781081656 in words is "eight hundred thirty-one billion, seven hundred eighty-one million, eighty-one thousand, six hundred fifty-six".