21766311227 has 4 divisors (see below), whose sum is σ = 21777763056. Its totient is φ = 21754859400.

The previous prime is 21766311223. The next prime is 21766311247. The reversal of 21766311227 is 72211366712.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21766311227 - 2² = 21766311223 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21766311221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5723063 + ... + 5726864.

It is an arithmetic number, because the mean of its divisors is an integer number (5444440764).

Almost surely, 2^21766311227 is an apocalyptic number.

21766311227 is a deficient number, since it is larger than the sum of its proper divisors (11451829).

21766311227 is a wasteful number, since it uses less digits than its factorization.

21766311227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11451828.

The product of its digits is 42336, while the sum is 38.

Adding to 21766311227 its reverse (72211366712), we get a palindrome (93977677939).

The spelling of 21766311227 in words is "twenty-one billion, seven hundred sixty-six million, three hundred eleven thousand, two hundred twenty-seven".