66655109712 has 80 divisors (see below), whose sum is σ = 174684533760. Its totient is φ = 21898944000.

The previous prime is 66655109693. The next prime is 66655109743. The reversal of 66655109712 is 21790155666.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 965962 + ... + 1032662.

It is an arithmetic number, because the mean of its divisors is an integer number (2183556672).

Almost surely, 2^66655109712 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 66655109712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87342266880).

66655109712 is an abundant number, since it is smaller than the sum of its proper divisors (108029424048).

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

66655109712 is a wasteful number, since it uses less digits than its factorization.

66655109712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67012 (or 67006 counting only the distinct ones).

The product of its (nonzero) digits is 680400, while the sum is 48.

The spelling of 66655109712 in words is "sixty-six billion, six hundred fifty-five million, one hundred nine thousand, seven hundred twelve".