66293680 has 40 divisors (see below), whose sum is σ = 155740032. Its totient is φ = 26241024.

The previous prime is 66293657. The next prime is 66293701. The reversal of 66293680 is 8639266.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3489 + ... + 12031.

Almost surely, 2^66293680 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 66293680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77870016).

66293680 is an abundant number, since it is smaller than the sum of its proper divisors (89446352).

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

66293680 is a wasteful number, since it uses less digits than its factorization.

66293680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8653 (or 8647 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 40.

The square root of 66293680 is about 8142.0930969868. The cubic root of 66293680 is about 404.7225249720.

The spelling of 66293680 in words is "sixty-six million, two hundred ninety-three thousand, six hundred eighty".