66378585 has 48 divisors (see below), whose sum is σ = 133068096. Its totient is φ = 28006272.

The previous prime is 66378577. The next prime is 66378589. The reversal of 66378585 is 58587366.

It is not a de Polignac number, because 66378585 - 2³ = 66378577 is a prime.

It is a super-2 number, since 2×66378585² = 8812233093204450, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66378589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6082 + ... + 13028.

It is an arithmetic number, because the mean of its divisors is an integer number (2772252).

Almost surely, 2^66378585 is an apocalyptic number.

66378585 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66378585 is an abundant number, since it is smaller than the sum of its proper divisors (66689511).

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

66378585 is a wasteful number, since it uses less digits than its factorization.

66378585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6982 (or 6975 counting only the distinct ones).

The product of its digits is 1209600, while the sum is 48.

The square root of 66378585 is about 8147.3053827631. The cubic root of 66378585 is about 404.8952327696.

The spelling of 66378585 in words is "sixty-six million, three hundred seventy-eight thousand, five hundred eighty-five".