65581660872 has 192 divisors, whose sum is σ = 223690346880. Its totient is φ = 16893950976.

The previous prime is 65581660847. The next prime is 65581660931. The reversal of 65581660872 is 27806618556.

65581660872 is a `hidden beast` number, since 6 + 558 + 1 + 6 + 6 + 0 + 87 + 2 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 165348 + ... + 398124.

It is an arithmetic number, because the mean of its divisors is an integer number (1165053890).

Almost surely, 2^65581660872 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 65581660872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111845173440).

65581660872 is an abundant number, since it is smaller than the sum of its proper divisors (158108686008).

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

65581660872 is a wasteful number, since it uses less digits than its factorization.

65581660872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232852 (or 232845 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 54.

The spelling of 65581660872 in words is "sixty-five billion, five hundred eighty-one million, six hundred sixty thousand, eight hundred seventy-two".