21226005 has 24 divisors (see below), whose sum is σ = 37241568. Its totient is φ = 11182176.

The previous prime is 21226001. The next prime is 21226019. The reversal of 21226005 is 50062212.

It is not a de Polignac number, because 21226005 - 2² = 21226001 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21226001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 894 + ... + 6576.

It is an arithmetic number, because the mean of its divisors is an integer number (1551732).

Almost surely, 2^21226005 is an apocalyptic number.

It is an amenable number.

21226005 is a deficient number, since it is larger than the sum of its proper divisors (16015563).

21226005 is a wasteful number, since it uses less digits than its factorization.

21226005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5777 (or 5774 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21226005 is about 4607.1688703585. The cubic root of 21226005 is about 276.8786193766.

Adding to 21226005 its reverse (50062212), we get a palindrome (71288217).

The spelling of 21226005 in words is "twenty-one million, two hundred twenty-six thousand, five".