66984331221 has 12 divisors (see below), whose sum is σ = 100961890848. Its totient is φ = 42714645864.

The previous prime is 66984331207. The next prime is 66984331231. The reversal of 66984331221 is 12213348966.

66984331221 is a `hidden beast` number, since 6 + 6 + 98 + 4 + 331 + 221 = 666.

It is not a de Polignac number, because 66984331221 - 2⁵ = 66984331189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66984331201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 161797695 + ... + 161798108.

It is an arithmetic number, because the mean of its divisors is an integer number (8413490904).

Almost surely, 2^66984331221 is an apocalyptic number.

It is an amenable number.

66984331221 is a deficient number, since it is larger than the sum of its proper divisors (33977559627).

66984331221 is a wasteful number, since it uses less digits than its factorization.

66984331221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323595832 (or 323595829 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The spelling of 66984331221 in words is "sixty-six billion, nine hundred eighty-four million, three hundred thirty-one thousand, two hundred twenty-one".