66815124480 has 968 divisors, whose sum is σ = 274139103672. Its totient is φ = 15479341056.

The previous prime is 66815124427. The next prime is 66815124517. The reversal of 66815124480 is 8442151866.

It is a happy number.

66815124480 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4897760256 + 61917364224 = 69984^2 + 248832^2 .

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 polite number, since it can be written in 87 ways as a sum of consecutive naturals, for example, 3930301432 + ... + 3930301448.

Almost surely, 2^66815124480 is an apocalyptic number.

66815124480 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 66815124480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137069551836).

66815124480 is an abundant number, since it is smaller than the sum of its proper divisors (207323979192).

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

66815124480 is an equidigital number, since it uses as much as digits as its factorization.

66815124480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 66815124480 in words is "sixty-six billion, eight hundred fifteen million, one hundred twenty-four thousand, four hundred eighty".