66935680 has 128 divisors (see below), whose sum is σ = 186439680. Its totient is φ = 22505472.

The previous prime is 66935653. The next prime is 66935699. The reversal of 66935680 is 8653966.

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 polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 300049 + ... + 300271.

It is an arithmetic number, because the mean of its divisors is an integer number (1456560).

Almost surely, 2^66935680 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 66935680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93219840).

66935680 is an abundant number, since it is smaller than the sum of its proper divisors (119504000).

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

66935680 is a wasteful number, since it uses less digits than its factorization.

66935680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 66935680 is about 8181.4228591364. The cubic root of 66935680 is about 406.0247988929.

The spelling of 66935680 in words is "sixty-six million, nine hundred thirty-five thousand, six hundred eighty".