8218421608717 has 16 divisors (see below), whose sum is σ = 8324382976000. Its totient is φ = 8113201947648.

The previous prime is 8218421608703. The next prime is 8218421608721. The reversal of 8218421608717 is 7178061248128.

It is a cyclic number.

It is not a de Polignac number, because 8218421608717 - 2¹⁹ = 8218421084429 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 (8218421638717) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21164293 + ... + 21549109.

It is an arithmetic number, because the mean of its divisors is an integer number (520273936000).

Almost surely, 2^{8218421608717} is an apocalyptic number.

It is an amenable number.

8218421608717 is a deficient number, since it is larger than the sum of its proper divisors (105961367283).

8218421608717 is a wasteful number, since it uses less digits than its factorization.

8218421608717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385780.

The product of its (nonzero) digits is 2408448, while the sum is 55.

The spelling of 8218421608717 in words is "eight trillion, two hundred eighteen billion, four hundred twenty-one million, six hundred eight thousand, seven hundred seventeen".