81551580776782 has 8 divisors (see below), whose sum is σ = 122360087777400. Its totient is φ = 40764884850984.

The previous prime is 81551580776779. The next prime is 81551580776807. The reversal of 81551580776782 is 28767708515518.

81551580776782 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

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, 5452759357 + ... + 5452774312.

It is an arithmetic number, because the mean of its divisors is an integer number (15295010972175).

Almost surely, 2^{81551580776782} is an apocalyptic number.

81551580776782 is a deficient number, since it is larger than the sum of its proper divisors (40808507000618).

81551580776782 is a wasteful number, since it uses less digits than its factorization.

81551580776782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10905537410.

The product of its (nonzero) digits is 263424000, while the sum is 70.

The spelling of 81551580776782 in words is "eighty-one trillion, five hundred fifty-one billion, five hundred eighty million, seven hundred seventy-six thousand, seven hundred eighty-two".