66106728 has 24 divisors (see below), whose sum is σ = 179039250. Its totient is φ = 22035552.

The previous prime is 66106723. The next prime is 66106759. The reversal of 66106728 is 82760166.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 44595684 + 21511044 = 6678^2 + 4638^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-3 number, since 3×66106728³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 66106692 and 66106701.

It is not an unprimeable number, because it can be changed into a prime (66106721) 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, 459003 + ... + 459146.

Almost surely, 2^66106728 is an apocalyptic number.

It is an amenable number.

66106728 is an abundant number, since it is smaller than the sum of its proper divisors (112932522).

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

66106728 is a wasteful number, since it uses less digits than its factorization.

66106728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918161 (or 918154 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 66106728 is about 8130.6044055777. The cubic root of 66106728 is about 404.3417198312.

The spelling of 66106728 in words is "sixty-six million, one hundred six thousand, seven hundred twenty-eight".