678856686420 has 96 divisors (see below), whose sum is σ = 2195575030656. Its totient is φ = 154890649600.

The previous prime is 678856686419. The next prime is 678856686523. The reversal of 678856686420 is 24686658876.

678856686420 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30240861 + ... + 30263300.

It is an arithmetic number, because the mean of its divisors is an integer number (22870573236).

Almost surely, 2^678856686420 is an apocalyptic number.

678856686420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

678856686420 is an abundant number, since it is smaller than the sum of its proper divisors (1516718344236).

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

678856686420 is a wasteful number, since it uses less digits than its factorization.

678856686420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60504201 (or 60504199 counting only the distinct ones).

The product of its (nonzero) digits is 185794560, while the sum is 66.

The spelling of 678856686420 in words is "six hundred seventy-eight billion, eight hundred fifty-six million, six hundred eighty-six thousand, four hundred twenty".