678699407680 has 504 divisors, whose sum is σ = 1972419422184. Its totient is φ = 221745807360.

The previous prime is 678699407657. The next prime is 678699407681. The reversal of 678699407680 is 86704996876.

It can be written as a sum of positive squares in 4 ways, for example, as 1594245184 + 677105162496 = 39928^2 + 822864^2 .

It is a Harshad number since it is a multiple of its sum of digits (70).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678699407681) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1099998732 + ... + 1099999348.

Almost surely, 2^678699407680 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 678699407680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (986209711092).

678699407680 is an abundant number, since it is smaller than the sum of its proper divisors (1293720014504).

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

678699407680 is a wasteful number, since it uses less digits than its factorization.

678699407680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783 (or 735 counting only the distinct ones).

The product of its (nonzero) digits is 219469824, while the sum is 70.

The spelling of 678699407680 in words is "six hundred seventy-eight billion, six hundred ninety-nine million, four hundred seven thousand, six hundred eighty".