77910781398912 has 3072 divisors, whose sum is σ = 323223892992000. Its totient is φ = 18066755911680.

The previous prime is 77910781398911. The next prime is 77910781398971. The reversal of 77910781398912 is 21989318701977.

77910781398912 is a `hidden beast` number, since 7 + 79 + 1 + 0 + 7 + 81 + 398 + 91 + 2 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77910781398911) 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 383 ways as a sum of consecutive naturals, for example, 56744923858 + ... + 56744925230.

It is an arithmetic number, because the mean of its divisors is an integer number (105216111000).

Almost surely, 2^{77910781398912} is an apocalyptic number.

77910781398912 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77910781398912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161611946496000).

77910781398912 is an abundant number, since it is smaller than the sum of its proper divisors (245313111593088).

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

77910781398912 is a wasteful number, since it uses less digits than its factorization.

77910781398912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1511 (or 1487 counting only the distinct ones).

The product of its (nonzero) digits is 96018048, while the sum is 72.

The spelling of 77910781398912 in words is "seventy-seven trillion, nine hundred ten billion, seven hundred eighty-one million, three hundred ninety-eight thousand, nine hundred twelve".