66580388 has 24 divisors (see below), whose sum is σ = 135996672. Its totient is φ = 27926784.

The previous prime is 66580387. The next prime is 66580411. The reversal of 66580388 is 88308566.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (66580387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23981 + ... + 26612.

It is an arithmetic number, because the mean of its divisors is an integer number (5666528).

Almost surely, 2^66580388 is an apocalyptic number.

It is an amenable number.

66580388 is an abundant number, since it is smaller than the sum of its proper divisors (69416284).

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

66580388 is a wasteful number, since it uses less digits than its factorization.

66580388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50651 (or 50649 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 44.

The square root of 66580388 is about 8159.6806310051. The cubic root of 66580388 is about 405.3051360978.

The spelling of 66580388 in words is "sixty-six million, five hundred eighty thousand, three hundred eighty-eight".