81780771800850 has 48 divisors (see below), whose sum is σ = 205672881896640. Its totient is φ = 21501047982400.

The previous prime is 81780771800843. The next prime is 81780771800941. The reversal of 81780771800850 is 5800817708718.

81780771800850 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×81780771800850³ (a number of 43 digits) contains 333 as substring.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 3839462205 + ... + 3839483504.

It is an arithmetic number, because the mean of its divisors is an integer number (4284851706180).

Almost surely, 2^{81780771800850} is an apocalyptic number.

81780771800850 is an abundant number, since it is smaller than the sum of its proper divisors (123892110095790).

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

81780771800850 is a wasteful number, since it uses less digits than its factorization.

81780771800850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7678945795 (or 7678945790 counting only the distinct ones).

The product of its (nonzero) digits is 7024640, while the sum is 60.

The spelling of 81780771800850 in words is "eighty-one trillion, seven hundred eighty billion, seven hundred seventy-one million, eight hundred thousand, eight hundred fifty".