66664857600 has 816 divisors, whose sum is σ = 269146434240. Its totient is φ = 16043212800.

The previous prime is 66664857583. The next prime is 66664857631. The reversal of 66664857600 is 675846666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 486604732 + ... + 486604868.

Almost surely, 2^66664857600 is an apocalyptic number.

66664857600 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66664857600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134573217120).

66664857600 is an abundant number, since it is smaller than the sum of its proper divisors (202481576640).

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

66664857600 is a wasteful number, since it uses less digits than its factorization.

66664857600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 54.

The spelling of 66664857600 in words is "sixty-six billion, six hundred sixty-four million, eight hundred fifty-seven thousand, six hundred".