66551984226 has 96 divisors (see below), whose sum is σ = 178100307840. Its totient is φ = 17490028032.

The previous prime is 66551984221. The next prime is 66551984243. The reversal of 66551984226 is 62248915566.

66551984226 is a `hidden beast` number, since 6 + 6 + 551 + 9 + 84 + 2 + 2 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (66551984221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 391770 + ... + 535338.

It is an arithmetic number, because the mean of its divisors is an integer number (1855211540).

Almost surely, 2^66551984226 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66551984226, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89050153920).

66551984226 is an abundant number, since it is smaller than the sum of its proper divisors (111548323614).

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

66551984226 is a wasteful number, since it uses less digits than its factorization.

66551984226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143880 (or 143877 counting only the distinct ones).

The product of its digits is 6220800, while the sum is 54.

The spelling of 66551984226 in words is "sixty-six billion, five hundred fifty-one million, nine hundred eighty-four thousand, two hundred twenty-six".