66986987317 has 4 divisors (see below), whose sum is σ = 67169513536. Its totient is φ = 66804461100.

The previous prime is 66986987297. The next prime is 66986987321. The reversal of 66986987317 is 71378968966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66986987317 - 2¹⁹ = 66986463029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66986988317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91262559 + ... + 91263292.

It is an arithmetic number, because the mean of its divisors is an integer number (16792378384).

Almost surely, 2^66986987317 is an apocalyptic number.

It is an amenable number.

66986987317 is a deficient number, since it is larger than the sum of its proper divisors (182526219).

66986987317 is a wasteful number, since it uses less digits than its factorization.

66986987317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182526218.

The product of its digits is 164602368, while the sum is 70.

The spelling of 66986987317 in words is "sixty-six billion, nine hundred eighty-six million, nine hundred eighty-seven thousand, three hundred seventeen".