66223398686172 has 96 divisors (see below), whose sum is σ = 190192895015424. Its totient is φ = 17464329043200.

The previous prime is 66223398686143. The next prime is 66223398686177. The reversal of 66223398686172 is 27168689332266.

It is a junction number, because it is equal to n+sod(n) for n = 66223398686097 and 66223398686106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66223398686177) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14138647 + ... + 18230417.

It is an arithmetic number, because the mean of its divisors is an integer number (1981175989744).

Almost surely, 2^{66223398686172} is an apocalyptic number.

It is an amenable number.

66223398686172 is an abundant number, since it is smaller than the sum of its proper divisors (123969496329252).

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

66223398686172 is a wasteful number, since it uses less digits than its factorization.

66223398686172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4106619 (or 4106617 counting only the distinct ones).

The product of its digits is 376233984, while the sum is 69.

The spelling of 66223398686172 in words is "sixty-six trillion, two hundred twenty-three billion, three hundred ninety-eight million, six hundred eighty-six thousand, one hundred seventy-two".