66840053760 has 576 divisors, whose sum is σ = 243198774000. Its totient is φ = 16955473920.

The previous prime is 66840053719. The next prime is 66840053771. The reversal of 66840053760 is 6735004866.

It can be written as a sum of positive squares in 8 ways, for example, as 24516043776 + 42324009984 = 156576^2 + 205728^2 .

It is a tau number, because it is divible by the number of its divisors (576).

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

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 47 ways as a sum of consecutive naturals, for example, 237864820 + ... + 237865100.

Almost surely, 2^66840053760 is an apocalyptic number.

66840053760 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 66840053760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121599387000).

66840053760 is an abundant number, since it is smaller than the sum of its proper divisors (176358720240).

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

66840053760 is a wasteful number, since it uses less digits than its factorization.

66840053760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 409 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 66840053760 in words is "sixty-six billion, eight hundred forty million, fifty-three thousand, seven hundred sixty".