66031728 has 40 divisors (see below), whose sum is σ = 194951808. Its totient is φ = 18866112.

The previous prime is 66031727. The next prime is 66031739. The reversal of 66031728 is 82713066.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66031727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97926 + ... + 98597.

Almost surely, 2^66031728 is an apocalyptic number.

It is an amenable number.

66031728 is an abundant number, since it is smaller than the sum of its proper divisors (128920080).

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

66031728 is a wasteful number, since it uses less digits than its factorization.

66031728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196541 (or 196535 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 66031728 is about 8125.9908934234. The cubic root of 66031728 is about 404.1887494978.

The spelling of 66031728 in words is "sixty-six million, thirty-one thousand, seven hundred twenty-eight".