66339640 has 64 divisors (see below), whose sum is σ = 161028000. Its totient is φ = 24514560.

The previous prime is 66339619. The next prime is 66339641. The reversal of 66339640 is 4693366.

66339640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 66339640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66339641) 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, 30096 + ... + 32224.

Almost surely, 2^66339640 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 66339640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80514000).

66339640 is an abundant number, since it is smaller than the sum of its proper divisors (94688360).

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

66339640 is a wasteful number, since it uses less digits than its factorization.

66339640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2200 (or 2196 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 37.

The square root of 66339640 is about 8144.9149780707. The cubic root of 66339640 is about 404.8160318761.

The spelling of 66339640 in words is "sixty-six million, three hundred thirty-nine thousand, six hundred forty".