66006421689600 has 1728 divisors, whose sum is σ = 282797080384000. Its totient is φ = 15058556190720.

The previous prime is 66006421689581. The next prime is 66006421689613. The reversal of 66006421689600 is 698612460066.

66006421689600 is a `hidden beast` number, since 6 + 6 + 0 + 0 + 6 + 4 + 21 + 6 + 8 + 9 + 600 = 666.

It is a tau number, because it is divible by the number of its divisors (1728).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 59092588242 + ... + 59092589358.

Almost surely, 2^{66006421689600} is an apocalyptic number.

66006421689600 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 66006421689600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141398540192000).

66006421689600 is an abundant number, since it is smaller than the sum of its proper divisors (216790658694400).

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

66006421689600 is a wasteful number, since it uses less digits than its factorization.

66006421689600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2170 (or 2131 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 54.

The spelling of 66006421689600 in words is "sixty-six trillion, six billion, four hundred twenty-one million, six hundred eighty-nine thousand, six hundred".