66817973409 has 8 divisors (see below), whose sum is σ = 97189779552. Its totient is φ = 40495741440.

The previous prime is 66817973377. The next prime is 66817973413. The reversal of 66817973409 is 90437971866.

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

It is not a de Polignac number, because 66817973409 - 2⁵ = 66817973377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66817973449) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1012393504 + ... + 1012393569.

It is an arithmetic number, because the mean of its divisors is an integer number (12148722444).

Almost surely, 2^66817973409 is an apocalyptic number.

It is an amenable number.

66817973409 is a deficient number, since it is larger than the sum of its proper divisors (30371806143).

66817973409 is a wasteful number, since it uses less digits than its factorization.

66817973409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2024787087.

The product of its (nonzero) digits is 13716864, while the sum is 60.

The spelling of 66817973409 in words is "sixty-six billion, eight hundred seventeen million, nine hundred seventy-three thousand, four hundred nine".