66931072 has 128 divisors (see below), whose sum is σ = 158508000. Its totient is φ = 27869184.

The previous prime is 66931069. The next prime is 66931087. The reversal of 66931072 is 27013966.

66931072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 916828 + ... + 916900.

Almost surely, 2^66931072 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 66931072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79254000).

66931072 is an abundant number, since it is smaller than the sum of its proper divisors (91576928).

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

66931072 is a wasteful number, since it uses less digits than its factorization.

66931072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 136 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 66931072 is about 8181.1412406827. The cubic root of 66931072 is about 406.0154814645.

The spelling of 66931072 in words is "sixty-six million, nine hundred thirty-one thousand, seventy-two".