66378474624 has 512 divisors, whose sum is σ = 225263001600. Its totient is φ = 16821043200.

The previous prime is 66378474611. The next prime is 66378474649. The reversal of 66378474624 is 42647487366.

It is a happy number.

It is a super-2 number, since 2×66378474624² (a number of 22 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

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 63 ways as a sum of consecutive naturals, for example, 366731814 + ... + 366731994.

It is an arithmetic number, because the mean of its divisors is an integer number (439966800).

Almost surely, 2^66378474624 is an apocalyptic number.

66378474624 is a gapful number since it is divisible by the number (64) 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 66378474624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112631500800).

66378474624 is an abundant number, since it is smaller than the sum of its proper divisors (158884526976).

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

66378474624 is a wasteful number, since it uses less digits than its factorization.

66378474624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452 (or 440 counting only the distinct ones).

The product of its digits is 32514048, while the sum is 57.

The spelling of 66378474624 in words is "sixty-six billion, three hundred seventy-eight million, four hundred seventy-four thousand, six hundred twenty-four".