66428872 has 8 divisors (see below), whose sum is σ = 124554150. Its totient is φ = 33214432.

The previous prime is 66428861. The next prime is 66428881. The reversal of 66428872 is 27882466.

It can be written as a sum of positive squares in only one way, i.e., 38613796 + 27815076 = 6214^2 + 5274^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4151797 + ... + 4151812.

Almost surely, 2^66428872 is an apocalyptic number.

It is an amenable number.

66428872 is a deficient number, since it is larger than the sum of its proper divisors (58125278).

66428872 is a wasteful number, since it uses less digits than its factorization.

66428872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8303615 (or 8303611 counting only the distinct ones).

The product of its digits is 258048, while the sum is 43.

The square root of 66428872 is about 8150.3909108705. The cubic root of 66428872 is about 404.9974536242.

The spelling of 66428872 in words is "sixty-six million, four hundred twenty-eight thousand, eight hundred seventy-two".