678801988 has 6 divisors (see below), whose sum is σ = 1187903486. Its totient is φ = 339400992.

The previous prime is 678801953. The next prime is 678801997. The reversal of 678801988 is 889108876.

It can be written as a sum of positive squares in only one way, i.e., 544195584 + 134606404 = 23328^2 + 11602^2 .

It is a super-5 number, since 5×678801988⁵ (a number of 45 digits) contains 55555 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84850245 + ... + 84850252.

Almost surely, 2^678801988 is an apocalyptic number.

It is an amenable number.

678801988 is a deficient number, since it is larger than the sum of its proper divisors (509101498).

678801988 is a wasteful number, since it uses less digits than its factorization.

678801988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169700501 (or 169700499 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 55.

The square root of 678801988 is about 26053.8286629816. The cubic root of 678801988 is about 878.8492137346.

The spelling of 678801988 in words is "six hundred seventy-eight million, eight hundred one thousand, nine hundred eighty-eight".