665407217112 has 128 divisors (see below), whose sum is σ = 1843536499200. Its totient is φ = 198464256000.

The previous prime is 665407217107. The next prime is 665407217129. The reversal of 665407217112 is 211712704566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4268608 + ... + 4421744.

It is an arithmetic number, because the mean of its divisors is an integer number (14402628900).

Almost surely, 2^665407217112 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 665407217112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (921768249600).

665407217112 is an abundant number, since it is smaller than the sum of its proper divisors (1178129282088).

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

665407217112 is a wasteful number, since it uses less digits than its factorization.

665407217112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153417 (or 153413 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 42.

The spelling of 665407217112 in words is "six hundred sixty-five billion, four hundred seven million, two hundred seventeen thousand, one hundred twelve".