21226417745 has 12 divisors (see below), whose sum is σ = 27581784156. Its totient is φ = 15674892480.

The previous prime is 21226417679. The next prime is 21226417783. The reversal of 21226417745 is 54771462212.

It can be written as a sum of positive squares in 6 ways, for example, as 3169239616 + 18057178129 = 56296^2 + 134377^2 .

It is not a de Polignac number, because 21226417745 - 2⁸ = 21226417489 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 12559166 + ... + 12560855.

It is an arithmetic number, because the mean of its divisors is an integer number (2298482013).

Almost surely, 2^21226417745 is an apocalyptic number.

It is an amenable number.

21226417745 is a deficient number, since it is larger than the sum of its proper divisors (6355366411).

21226417745 is a wasteful number, since it uses less digits than its factorization.

21226417745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25120052 (or 25120039 counting only the distinct ones).

The product of its digits is 188160, while the sum is 41.

Adding to 21226417745 its reverse (54771462212), we get a palindrome (75997879957).

The spelling of 21226417745 in words is "twenty-one billion, two hundred twenty-six million, four hundred seventeen thousand, seven hundred forty-five".