665471718912 has 1280 divisors, whose sum is σ = 2482541107200. Its totient is φ = 157367992320.

The previous prime is 665471718889. The next prime is 665471718917. The reversal of 665471718912 is 219817174566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665471718917) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 9116050908 + ... + 9116050980.

It is an arithmetic number, because the mean of its divisors is an integer number (1939485240).

Almost surely, 2^665471718912 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 665471718912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1241270553600).

665471718912 is an abundant number, since it is smaller than the sum of its proper divisors (1817069388288).

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

665471718912 is an equidigital number, since it uses as much as digits as its factorization.

665471718912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161 (or 109 counting only the distinct ones).

The product of its digits is 5080320, while the sum is 57.

The spelling of 665471718912 in words is "six hundred sixty-five billion, four hundred seventy-one million, seven hundred eighteen thousand, nine hundred twelve".