66919861220 has 12 divisors (see below), whose sum is σ = 140531708604. Its totient is φ = 26767944480.

The previous prime is 66919861201. The next prime is 66919861237. The reversal of 66919861220 is 2216891966.

It can be written as a sum of positive squares in 2 ways, for example, as 10681635904 + 56238225316 = 103352^2 + 237146^2 .

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1672996511 + ... + 1672996550.

It is an arithmetic number, because the mean of its divisors is an integer number (11710975717).

Almost surely, 2^66919861220 is an apocalyptic number.

It is an amenable number.

66919861220 is an abundant number, since it is smaller than the sum of its proper divisors (73611847384).

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

66919861220 is a wasteful number, since it uses less digits than its factorization.

66919861220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3345993070 (or 3345993068 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 50.

The spelling of 66919861220 in words is "sixty-six billion, nine hundred nineteen million, eight hundred sixty-one thousand, two hundred twenty".