21271182716 has 12 divisors (see below), whose sum is σ = 42542365488. Its totient is φ = 9116221152.

The previous prime is 21271182707. The next prime is 21271182773. The reversal of 21271182716 is 61728117212.

21271182716 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21271182716.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 379842521 + ... + 379842576.

It is an arithmetic number, because the mean of its divisors is an integer number (3545197124).

Almost surely, 2^21271182716 is an apocalyptic number.

It is an amenable number.

21271182716 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21271182716 is a wasteful number, since it uses less digits than its factorization.

21271182716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 759685108 (or 759685106 counting only the distinct ones).

The product of its digits is 18816, while the sum is 38.

Adding to 21271182716 its reverse (61728117212), we get a palindrome (82999299928).

The spelling of 21271182716 in words is "twenty-one billion, two hundred seventy-one million, one hundred eighty-two thousand, seven hundred sixteen".