66570917994720 has 336 divisors, whose sum is σ = 236153475229392. Its totient is φ = 17725846118400.

The previous prime is 66570917994667. The next prime is 66570917994739. The reversal of 66570917994720 is 2749971907566.

66570917994720 is a `hidden beast` number, since 6 + 6 + 57 + 0 + 9 + 17 + 99 + 472 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 78074695 + ... + 78922745.

It is an arithmetic number, because the mean of its divisors is an integer number (702837723897).

Almost surely, 2^{66570917994720} is an apocalyptic number.

66570917994720 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 66570917994720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118076737614696).

66570917994720 is an abundant number, since it is smaller than the sum of its proper divisors (169582557234672).

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

66570917994720 is an equidigital number, since it uses as much as digits as its factorization.

66570917994720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848757 (or 848734 counting only the distinct ones).

The product of its (nonzero) digits is 360067680, while the sum is 72.

The spelling of 66570917994720 in words is "sixty-six trillion, five hundred seventy billion, nine hundred seventeen million, nine hundred ninety-four thousand, seven hundred twenty".