678728655 has 48 divisors (see below), whose sum is σ = 1358925984. Its totient is φ = 309719040.

The previous prime is 678728647. The next prime is 678728711. The reversal of 678728655 is 556827876.

It is not a de Polignac number, because 678728655 - 2³ = 678728647 is a prime.

It is a super-3 number, since 3×678728655³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 31914 + ... + 48743.

It is an arithmetic number, because the mean of its divisors is an integer number (28310958).

Almost surely, 2^678728655 is an apocalyptic number.

678728655 is an abundant number, since it is smaller than the sum of its proper divisors (680197329).

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

678728655 is a wasteful number, since it uses less digits than its factorization.

678728655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80696 (or 80693 counting only the distinct ones).

The product of its digits is 5644800, while the sum is 54.

The square root of 678728655 is about 26052.4212886250. The cubic root of 678728655 is about 878.8175643623.

The spelling of 678728655 in words is "six hundred seventy-eight million, seven hundred twenty-eight thousand, six hundred fifty-five".