665511986160 has 800 divisors, whose sum is σ = 2826465523200. Its totient is φ = 141737195520.

The previous prime is 665511986159. The next prime is 665511986201. The reversal of 665511986160 is 61689115566.

665511986160 is a `hidden beast` number, since 6 + 6 + 5 + 5 + 1 + 19 + 8 + 616 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 665511986097 and 665511986106.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 52565911 + ... + 52578569.

It is an arithmetic number, because the mean of its divisors is an integer number (3533081904).

Almost surely, 2^665511986160 is an apocalyptic number.

665511986160 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 665511986160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1413232761600).

665511986160 is an abundant number, since it is smaller than the sum of its proper divisors (2160953537040).

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

665511986160 is a wasteful number, since it uses less digits than its factorization.

665511986160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12771 (or 12756 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 54.

The spelling of 665511986160 in words is "six hundred sixty-five billion, five hundred eleven million, nine hundred eighty-six thousand, one hundred sixty".