81680514782 has 8 divisors (see below), whose sum is σ = 123605027136. Its totient is φ = 40478839072.

The previous prime is 81680514781. The next prime is 81680514809. The reversal of 81680514782 is 28741508618.

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

It is a self number, because there is not a number n which added to its sum of digits gives 81680514782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81680514781) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 180708878 + ... + 180709329.

It is an arithmetic number, because the mean of its divisors is an integer number (15450628392).

Almost surely, 2^81680514782 is an apocalyptic number.

81680514782 is a deficient number, since it is larger than the sum of its proper divisors (41924512354).

81680514782 is a wasteful number, since it uses less digits than its factorization.

81680514782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361418322.

The product of its (nonzero) digits is 860160, while the sum is 50.

The spelling of 81680514782 in words is "eighty-one billion, six hundred eighty million, five hundred fourteen thousand, seven hundred eighty-two".