66312422172 has 144 divisors (see below), whose sum is σ = 184411019520. Its totient is φ = 20600918784.

The previous prime is 66312422129. The next prime is 66312422219. The reversal of 66312422172 is 27122421366.

66312422172 is a `hidden beast` number, since 6 + 63 + 1 + 2 + 422 + 172 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 47 ways as a sum of consecutive naturals, for example, 3204523 + ... + 3225149.

It is an arithmetic number, because the mean of its divisors is an integer number (1280632080).

Almost surely, 2^66312422172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66312422172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92205509760).

66312422172 is an abundant number, since it is smaller than the sum of its proper divisors (118098597348).

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

66312422172 is a wasteful number, since it uses less digits than its factorization.

66312422172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20777 (or 20752 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The spelling of 66312422172 in words is "sixty-six billion, three hundred twelve million, four hundred twenty-two thousand, one hundred seventy-two".