21117816327 has 16 divisors (see below), whose sum is σ = 29747773440. Its totient is φ = 13303860192.

The previous prime is 21117816299. The next prime is 21117816337. The reversal of 21117816327 is 72361871112.

It is a happy number.

It is not a de Polignac number, because 21117816327 - 2⁷ = 21117816199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21117816337) 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 15 ways as a sum of consecutive naturals, for example, 2578183 + ... + 2586360.

It is an arithmetic number, because the mean of its divisors is an integer number (1859235840).

Almost surely, 2^21117816327 is an apocalyptic number.

21117816327 is a deficient number, since it is larger than the sum of its proper divisors (8629957113).

21117816327 is a wasteful number, since it uses less digits than its factorization.

21117816327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5164622.

The product of its digits is 28224, while the sum is 39.

The spelling of 21117816327 in words is "twenty-one billion, one hundred seventeen million, eight hundred sixteen thousand, three hundred twenty-seven".