77321756666880 has 880 divisors, whose sum is σ = 302461256148480. Its totient is φ = 18732581683200.

The previous prime is 77321756666857. The next prime is 77321756666899. The reversal of 77321756666880 is 8866665712377.

77321756666880 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (880).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 77321756666799 and 77321756666808.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8535347791 + ... + 8535356849.

It is an arithmetic number, because the mean of its divisors is an integer number (343705972896).

Almost surely, 2^{77321756666880} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77321756666880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151230628074240).

77321756666880 is an abundant number, since it is smaller than the sum of its proper divisors (225139499481600).

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

77321756666880 is a wasteful number, since it uses less digits than its factorization.

77321756666880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10978 (or 10951 counting only the distinct ones).

The product of its (nonzero) digits is 853493760, while the sum is 72.

The spelling of 77321756666880 in words is "seventy-seven trillion, three hundred twenty-one billion, seven hundred fifty-six million, six hundred sixty-six thousand, eight hundred eighty".