21916998917 has 8 divisors (see below), whose sum is σ = 23961323232. Its totient is φ = 19881319600.

The previous prime is 21916998913. The next prime is 21916998919. The reversal of 21916998917 is 71989961912.

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 21916998917 - 2² = 21916998913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21916998917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21916998911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2155943 + ... + 2166084.

It is an arithmetic number, because the mean of its divisors is an integer number (2995165404).

Almost surely, 2^21916998917 is an apocalyptic number.

It is an amenable number.

21916998917 is a deficient number, since it is larger than the sum of its proper divisors (2044324315).

21916998917 is a wasteful number, since it uses less digits than its factorization.

21916998917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4322499.

The product of its digits is 4408992, while the sum is 62.

The spelling of 21916998917 in words is "twenty-one billion, nine hundred sixteen million, nine hundred ninety-eight thousand, nine hundred seventeen".