678791680 has 80 divisors (see below), whose sum is σ = 1860059520. Its totient is φ = 232722432.

The previous prime is 678791651. The next prime is 678791689. The reversal of 678791680 is 86197876.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (678791689) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1020 + ... + 36859.

It is an arithmetic number, because the mean of its divisors is an integer number (23250744).

Almost surely, 2^678791680 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 678791680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (930029760).

678791680 is an abundant number, since it is smaller than the sum of its proper divisors (1181267840).

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

678791680 is an equidigital number, since it uses as much as digits as its factorization.

678791680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37909 (or 37893 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 52.

The square root of 678791680 is about 26053.6308410171. The cubic root of 678791680 is about 878.8447651012.

The spelling of 678791680 in words is "six hundred seventy-eight million, seven hundred ninety-one thousand, six hundred eighty".