678564864 has 198 divisors, whose sum is σ = 2054741754. Its totient is φ = 223948800.

The previous prime is 678564847. The next prime is 678564893. The reversal of 678564864 is 468465876.

678564864 is a `hidden beast` number, since 6 + 78 + 564 + 8 + 6 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 671846400 + 6718464 = 25920^2 + 2592^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 678564864.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 6718414 + ... + 6718514.

Almost surely, 2^678564864 is an apocalyptic number.

678564864 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 678564864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1027370877).

678564864 is an abundant number, since it is smaller than the sum of its proper divisors (1376176890).

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

678564864 is an frugal number, since it uses more digits than its factorization.

678564864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 106 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 54.

The square root of 678564864 is about 26049.2776099453. The cubic root of 678564864 is about 878.7468665035.

The spelling of 678564864 in words is "six hundred seventy-eight million, five hundred sixty-four thousand, eight hundred sixty-four".