66566612412 has 144 divisors (see below), whose sum is σ = 178230780000. Its totient is φ = 20916392448.

The previous prime is 66566612389. The next prime is 66566612417. The reversal of 66566612412 is 21421666566.

It is a super-2 number, since 2×66566612412² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66566612417) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9174178 + ... + 9181430.

It is an arithmetic number, because the mean of its divisors is an integer number (1237713750).

Almost surely, 2^66566612412 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 66566612412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89115390000).

66566612412 is an abundant number, since it is smaller than the sum of its proper divisors (111664167588).

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

66566612412 is a wasteful number, since it uses less digits than its factorization.

66566612412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7500 (or 7495 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The spelling of 66566612412 in words is "sixty-six billion, five hundred sixty-six million, six hundred twelve thousand, four hundred twelve".