66663408 has 80 divisors (see below), whose sum is σ = 198003200. Its totient is φ = 18931968.

The previous prime is 66663383. The next prime is 66663413. The reversal of 66663408 is 80436666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66366 + ... + 67362.

It is an arithmetic number, because the mean of its divisors is an integer number (2475040).

Almost surely, 2^66663408 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 66663408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99001600).

66663408 is an abundant number, since it is smaller than the sum of its proper divisors (131339792).

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

66663408 is a wasteful number, since it uses less digits than its factorization.

66663408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1214 (or 1208 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 39.

The square root of 66663408 is about 8164.7662550743. The cubic root of 66663408 is about 405.4735263076.

The spelling of 66663408 in words is "sixty-six million, six hundred sixty-three thousand, four hundred eight".