678218553 has 18 divisors (see below), whose sum is σ = 1040669214. Its totient is φ = 425547264.

The previous prime is 678218477. The next prime is 678218579. The reversal of 678218553 is 355812876.

678218553 is a `hidden beast` number, since 6 + 7 + 82 + 18 + 553 = 666.

678218553 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 421193529 + 257025024 = 20523^2 + 16032^2 .

It is not a de Polignac number, because 678218553 - 2¹⁶ = 678153017 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 678218499 and 678218508.

It is not an unprimeable number, because it can be changed into a prime (678218753) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 127776 + ... + 132977.

Almost surely, 2^678218553 is an apocalyptic number.

It is an amenable number.

678218553 is a deficient number, since it is larger than the sum of its proper divisors (362450661).

678218553 is a wasteful number, since it uses less digits than its factorization.

678218553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260793 (or 260773 counting only the distinct ones).

The product of its digits is 403200, while the sum is 45.

The square root of 678218553 is about 26042.6295331328. The cubic root of 678218553 is about 878.5973492367.

The spelling of 678218553 in words is "six hundred seventy-eight million, two hundred eighteen thousand, five hundred fifty-three".