66844884985 has 8 divisors (see below), whose sum is σ = 81727331400. Its totient is φ = 52466928384.

The previous prime is 66844884973. The next prime is 66844884991. The reversal of 66844884985 is 58948844866.

It can be written as a sum of positive squares in 4 ways, for example, as 8244095209 + 58600789776 = 90797^2 + 242076^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66844884985 - 2²¹ = 66842787833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126122160 + ... + 126122689.

It is an arithmetic number, because the mean of its divisors is an integer number (10215916425).

Almost surely, 2^66844884985 is an apocalyptic number.

It is an amenable number.

66844884985 is a deficient number, since it is larger than the sum of its proper divisors (14882446415).

66844884985 is a wasteful number, since it uses less digits than its factorization.

66844884985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252244907.

The product of its digits is 424673280, while the sum is 70.

The spelling of 66844884985 in words is "sixty-six billion, eight hundred forty-four million, eight hundred eighty-four thousand, nine hundred eighty-five".