678881728 has 42 divisors (see below), whose sum is σ = 1540858488. Its totient is φ = 290712960.

The previous prime is 678881713. The next prime is 678881729. The reversal of 678881728 is 827188876.

It is a super-2 number, since 2×678881728² = 921760801224531968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678881729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 550873 + ... + 552103.

Almost surely, 2^678881728 is an apocalyptic number.

It is an amenable number.

678881728 is an abundant number, since it is smaller than the sum of its proper divisors (861976760).

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

678881728 is an frugal number, since it uses more digits than its factorization.

678881728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2481 (or 1240 counting only the distinct ones).

The product of its digits is 2408448, while the sum is 55.

The square root of 678881728 is about 26055.3589113641. The cubic root of 678881728 is about 878.8836256807.

The spelling of 678881728 in words is "six hundred seventy-eight million, eight hundred eighty-one thousand, seven hundred twenty-eight".