678778761024 has 420 divisors, whose sum is σ = 2520681157764. Its totient is φ = 179017703424.

The previous prime is 678778761019. The next prime is 678778761041. The reversal of 678778761024 is 420167877876.

678778761024 is a `hidden beast` number, since 6 + 7 + 8 + 7 + 7 + 8 + 7 + 610 + 2 + 4 = 666.

678778761024 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 32555706624 + 646223054400 = 180432^2 + 803880^2 .

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 59 ways as a sum of consecutive naturals, for example, 3199432 + ... + 3404984.

Almost surely, 2^678778761024 is an apocalyptic number.

678778761024 is a gapful number since it is divisible by the number (64) 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 678778761024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1260340578882).

678778761024 is an abundant number, since it is smaller than the sum of its proper divisors (1841902396740).

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

678778761024 is a wasteful number, since it uses less digits than its factorization.

678778761024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205604 (or 205578 counting only the distinct ones).

The product of its (nonzero) digits is 44255232, while the sum is 63.

The spelling of 678778761024 in words is "six hundred seventy-eight billion, seven hundred seventy-eight million, seven hundred sixty-one thousand, twenty-four".