66717128 has 16 divisors (see below), whose sum is σ = 125183580. Its totient is φ = 33334848.

The previous prime is 66717107. The next prime is 66717137. The reversal of 66717128 is 82171766.

66717128 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 2 ways, for example, as 55681444 + 11035684 = 7462^2 + 3322^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66717091 and 66717100.

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 in 3 ways as a sum of consecutive naturals, for example, 16526 + ... + 20162.

Almost surely, 2^66717128 is an apocalyptic number.

It is an amenable number.

66717128 is a deficient number, since it is larger than the sum of its proper divisors (58466452).

66717128 is a wasteful number, since it uses less digits than its factorization.

66717128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5936 (or 5932 counting only the distinct ones).

The product of its digits is 28224, while the sum is 38.

The square root of 66717128 is about 8168.0553377166. The cubic root of 66717128 is about 405.5824125775.

The spelling of 66717128 in words is "sixty-six million, seven hundred seventeen thousand, one hundred twenty-eight".