66021298560 has 1280 divisors, whose sum is σ = 284359680000. Its totient is φ = 14582550528.

The previous prime is 66021298507. The next prime is 66021298573. The reversal of 66021298560 is 6589212066.

66021298560 is a `hidden beast` number, since 6 + 60 + 2 + 1 + 29 + 8 + 560 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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 159 ways as a sum of consecutive naturals, for example, 835712601 + ... + 835712679.

It is an arithmetic number, because the mean of its divisors is an integer number (222156000).

Almost surely, 2^66021298560 is an apocalyptic number.

66021298560 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 66021298560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142179840000).

66021298560 is an abundant number, since it is smaller than the sum of its proper divisors (218338381440).

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

66021298560 is an equidigital number, since it uses as much as digits as its factorization.

66021298560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178 (or 143 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 66021298560 in words is "sixty-six billion, twenty-one million, two hundred ninety-eight thousand, five hundred sixty".