81904000782 has 8 divisors (see below), whose sum is σ = 163808001576. Its totient is φ = 27301333592.

The previous prime is 81904000769. The next prime is 81904000813. The reversal of 81904000782 is 28700040918.

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

81904000782 is an admirable number.

It is a super-2 number, since 2×81904000782² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81904000782.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6825333393 + ... + 6825333404.

It is an arithmetic number, because the mean of its divisors is an integer number (20476000197).

Almost surely, 2^81904000782 is an apocalyptic number.

81904000782 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81904000782 is a wasteful number, since it uses less digits than its factorization.

81904000782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13650666802.

The product of its (nonzero) digits is 32256, while the sum is 39.

The spelling of 81904000782 in words is "eighty-one billion, nine hundred four million, seven hundred eighty-two", and thus it is an aban number.