77678171486478 has 48 divisors (see below), whose sum is σ = 174675880470000. Its totient is φ = 25871992862976.

The previous prime is 77678171486477. The next prime is 77678171486507. The reversal of 77678171486478 is 87468417187677.

77678171486478 is a `hidden beast` number, since 7 + 7 + 6 + 78 + 1 + 71 + 4 + 8 + 6 + 478 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a junction number, because it is equal to n+sod(n) for n = 77678171486397 and 77678171486406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77678171486477) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63376825 + ... + 64590852.

It is an arithmetic number, because the mean of its divisors is an integer number (3639080843125).

Almost surely, 2^{77678171486478} is an apocalyptic number.

77678171486478 is an abundant number, since it is smaller than the sum of its proper divisors (96997708983522).

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

77678171486478 is a wasteful number, since it uses less digits than its factorization.

77678171486478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127968943 (or 127968931 counting only the distinct ones).

The product of its digits is 4956585984, while the sum is 81.

The spelling of 77678171486478 in words is "seventy-seven trillion, six hundred seventy-eight billion, one hundred seventy-one million, four hundred eighty-six thousand, four hundred seventy-eight".