66404580 has 48 divisors (see below), whose sum is σ = 202837824. Its totient is φ = 16097920.

The previous prime is 66404557. The next prime is 66404581. The reversal of 66404580 is 8540466.

It is a happy number.

66404580 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (66404581) by changing a digit.

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, 49647 + ... + 50966.

It is an arithmetic number, because the mean of its divisors is an integer number (4225788).

Almost surely, 2^66404580 is an apocalyptic number.

66404580 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66404580 is an abundant number, since it is smaller than the sum of its proper divisors (136433244).

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

66404580 is a wasteful number, since it uses less digits than its factorization.

66404580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100636 (or 100634 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 66404580 is about 8148.9005393366. The cubic root of 66404580 is about 404.9480805262.

The spelling of 66404580 in words is "sixty-six million, four hundred four thousand, five hundred eighty".