678028730625 has 45 divisors (see below), whose sum is σ = 1223938271413. Its totient is φ = 361582386000.

The previous prime is 678028730623. The next prime is 678028730629. The reversal of 678028730625 is 526037820876.

The square root of 678028730625 is 823425.

It is a perfect power (a square), and thus also a powerful number.

678028730625 is a `hidden beast` number, since 6 + 7 + 8 + 0 + 2 + 8 + 7 + 3 + 0 + 625 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 53157452481 + 624871278144 = 230559^2 + 790488^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 678028730625 - 2¹ = 678028730623 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678028730623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 61751386 + ... + 61762364.

Almost surely, 2^678028730625 is an apocalyptic number.

678028730625 is the 823425-th square number.

678028730625 is the 411713-rd centered octagonal number.

It is an amenable number.

678028730625 is a deficient number, since it is larger than the sum of its proper divisors (545909540788).

678028730625 is an frugal number, since it uses more digits than its factorization.

678028730625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21984 (or 10987 counting only the distinct ones).

The product of its (nonzero) digits is 6773760, while the sum is 54.

The spelling of 678028730625 in words is "six hundred seventy-eight billion, twenty-eight million, seven hundred thirty thousand, six hundred twenty-five".