21375618717 has 8 divisors (see below), whose sum is σ = 28501521280. Its totient is φ = 14250064320.

The previous prime is 21375618703. The next prime is 21375618727. The reversal of 21375618717 is 71781657312.

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

It is not a de Polignac number, because 21375618717 - 2⁶ = 21375618653 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 (21375618727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 143292 + ... + 251562.

It is an arithmetic number, because the mean of its divisors is an integer number (3562690160).

Almost surely, 2^21375618717 is an apocalyptic number.

It is an amenable number.

21375618717 is a deficient number, since it is larger than the sum of its proper divisors (7125902563).

21375618717 is a wasteful number, since it uses less digits than its factorization.

21375618717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174083.

The product of its digits is 493920, while the sum is 48.

The spelling of 21375618717 in words is "twenty-one billion, three hundred seventy-five million, six hundred eighteen thousand, seven hundred seventeen".