66585576960 has 640 divisors, whose sum is σ = 273803904000. Its totient is φ = 15210602496.

The previous prime is 66585576907. The next prime is 66585576971. The reversal of 66585576960 is 6967558566.

66585576960 is a `hidden beast` number, since 6 + 6 + 58 + 5 + 576 + 9 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 39190191 + ... + 39191889.

It is an arithmetic number, because the mean of its divisors is an integer number (427818600).

Almost surely, 2^66585576960 is an apocalyptic number.

66585576960 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 66585576960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136901952000).

66585576960 is an abundant number, since it is smaller than the sum of its proper divisors (207218327040).

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

66585576960 is an frugal number, since it uses more digits than its factorization.

66585576960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1750 (or 1716 counting only the distinct ones).

The product of its (nonzero) digits is 81648000, while the sum is 63.

It can be divided in two parts, 66585 and 576960, that added together give a triangular number (643545 = T₁₁₃₄).

The spelling of 66585576960 in words is "sixty-six billion, five hundred eighty-five million, five hundred seventy-six thousand, nine hundred sixty".