648278028 has 18 divisors (see below), whose sum is σ = 1638702884. Its totient is φ = 216092664.

The previous prime is 648278027. The next prime is 648278039. The reversal of 648278028 is 820872846.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (648278021) by changing a digit.

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 in 5 ways as a sum of consecutive naturals, for example, 9003826 + ... + 9003897.

Almost surely, 2^648278028 is an apocalyptic number.

It is an amenable number.

648278028 is an abundant number, since it is smaller than the sum of its proper divisors (990424856).

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

648278028 is a wasteful number, since it uses less digits than its factorization.

648278028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18007733 (or 18007728 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 45.

The square root of 648278028 is about 25461.3045227459. The cubic root of 648278028 is about 865.4734855267.

The spelling of 648278028 in words is "six hundred forty-eight million, two hundred seventy-eight thousand, twenty-eight".