66287319840 has 576 divisors, whose sum is σ = 274098504960. Its totient is φ = 14656204800.

The previous prime is 66287319817. The next prime is 66287319851. The reversal of 66287319840 is 4891378266.

66287319840 is a `hidden beast` number, since 6 + 6 + 287 + 319 + 8 + 40 = 666.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 29059500 + ... + 29061780.

It is an arithmetic number, because the mean of its divisors is an integer number (475865460).

Almost surely, 2^66287319840 is an apocalyptic number.

66287319840 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 66287319840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137049252480).

66287319840 is an abundant number, since it is smaller than the sum of its proper divisors (207811185120).

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

66287319840 is a wasteful number, since it uses less digits than its factorization.

66287319840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2374 (or 2329 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 54.

The spelling of 66287319840 in words is "sixty-six billion, two hundred eighty-seven million, three hundred nineteen thousand, eight hundred forty".