678771555840 has 960 divisors, whose sum is σ = 2797718077440. Its totient is φ = 148821442560.

The previous prime is 678771555823. The next prime is 678771555853. The reversal of 678771555840 is 48555177876.

678771555840 is a `hidden beast` number, since 6 + 7 + 8 + 7 + 71 + 5 + 558 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 634958826 + ... + 634959894.

It is an arithmetic number, because the mean of its divisors is an integer number (2914289664).

Almost surely, 2^678771555840 is an apocalyptic number.

678771555840 is a gapful number since it is divisible by the number (60) 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 678771555840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1398859038720).

678771555840 is an abundant number, since it is smaller than the sum of its proper divisors (2118946521600).

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

678771555840 is a wasteful number, since it uses less digits than its factorization.

678771555840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263 (or 1244 counting only the distinct ones).

The product of its (nonzero) digits is 65856000, while the sum is 63.

The spelling of 678771555840 in words is "six hundred seventy-eight billion, seven hundred seventy-one million, five hundred fifty-five thousand, eight hundred forty".