66670928 has 30 divisors (see below), whose sum is σ = 135052554. Its totient is φ = 31882048.

The previous prime is 66670921. The next prime is 66670931. The reversal of 66670928 is 82907666.

66670928 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 46348864 + 20322064 = 6808^2 + 4508^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66670921) 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, 4526 + ... + 12402.

Almost surely, 2^66670928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66670928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67526277).

66670928 is an abundant number, since it is smaller than the sum of its proper divisors (68381626).

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

66670928 is a wasteful number, since it uses less digits than its factorization.

66670928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7931 (or 7902 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 44.

The square root of 66670928 is about 8165.2267574146. The cubic root of 66670928 is about 405.4887722842.

The spelling of 66670928 in words is "sixty-six million, six hundred seventy thousand, nine hundred twenty-eight".