66208240 has 80 divisors (see below), whose sum is σ = 177131520. Its totient is φ = 22544640.

The previous prime is 66208229. The next prime is 66208253. The reversal of 66208240 is 4280266.

66208240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 66208199 and 66208208.

It is a congruent number.

It is an unprimeable number.

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, 106651 + ... + 107269.

It is an arithmetic number, because the mean of its divisors is an integer number (2214144).

Almost surely, 2^66208240 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 66208240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88565760).

66208240 is an abundant number, since it is smaller than the sum of its proper divisors (110923280).

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

66208240 is a wasteful number, since it uses less digits than its factorization.

66208240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 830 (or 824 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 66208240 is about 8136.8445972625. The cubic root of 66208240 is about 404.5485799914.

The spelling of 66208240 in words is "sixty-six million, two hundred eight thousand, two hundred forty".