65666980872 has 96 divisors (see below), whose sum is σ = 187349448000. Its totient is φ = 20721329280.

The previous prime is 65666980849. The next prime is 65666980889. The reversal of 65666980872 is 27808966656.

It is a super-2 number, since 2×65666980872² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

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, 1871829 + ... + 1906587.

It is an arithmetic number, because the mean of its divisors is an integer number (1951556750).

Almost surely, 2^65666980872 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 65666980872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93674724000).

65666980872 is an abundant number, since it is smaller than the sum of its proper divisors (121682467128).

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

65666980872 is a wasteful number, since it uses less digits than its factorization.

65666980872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36171 (or 36164 counting only the distinct ones).

The product of its (nonzero) digits is 52254720, while the sum is 63.

The spelling of 65666980872 in words is "sixty-five billion, six hundred sixty-six million, nine hundred eighty thousand, eight hundred seventy-two".