665705131646976 has 336 divisors, whose sum is σ = 1943873304422400. Its totient is φ = 219509566341120.

The previous prime is 665705131646969. The next prime is 665705131647067. The reversal of 665705131646976 is 679646131507566.

665705131646976 is a `hidden beast` number, since 6 + 6 + 5 + 7 + 0 + 513 + 16 + 4 + 6 + 97 + 6 = 666.

It is a super-2 number, since 2×665705131646976² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2538102721 + ... + 2538364991.

Almost surely, 2^{665705131646976} 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 665705131646976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (971936652211200).

665705131646976 is an abundant number, since it is smaller than the sum of its proper divisors (1278168172775424).

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

665705131646976 is a wasteful number, since it uses less digits than its factorization.

665705131646976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262675 (or 262648 counting only the distinct ones).

The product of its (nonzero) digits is 1028764800, while the sum is 72.

The spelling of 665705131646976 in words is "six hundred sixty-five trillion, seven hundred five billion, one hundred thirty-one million, six hundred forty-six thousand, nine hundred seventy-six".