66863808 has 168 divisors, whose sum is σ = 213731856. Its totient is φ = 19814400.

The previous prime is 66863803. The next prime is 66863827. The reversal of 66863808 is 80836866.

66863808 is a `hidden beast` number, since 6 + 6 + 8 + 638 + 0 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (66863803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 386410 + ... + 386582.

Almost surely, 2^66863808 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 66863808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106865928).

66863808 is an abundant number, since it is smaller than the sum of its proper divisors (146868048).

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

66863808 is a wasteful number, since it uses less digits than its factorization.

66863808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263 (or 250 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 66863808 is about 8177.0292894180. The cubic root of 66863808 is about 405.8794241829.

The spelling of 66863808 in words is "sixty-six million, eight hundred sixty-three thousand, eight hundred eight".