21226345 has 24 divisors (see below), whose sum is σ = 29985984. Its totient is φ = 14129856.

The previous prime is 21226327. The next prime is 21226367. The reversal of 21226345 is 54362212.

It is not a de Polignac number, because 21226345 - 2⁹ = 21225833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47694 + ... + 48136.

It is an arithmetic number, because the mean of its divisors is an integer number (1249416).

Almost surely, 2^21226345 is an apocalyptic number.

It is an amenable number.

21226345 is a deficient number, since it is larger than the sum of its proper divisors (8759639).

21226345 is an equidigital number, since it uses as much as digits as its factorization.

21226345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 492 counting only the distinct ones).

The product of its digits is 2880, while the sum is 25.

The square root of 21226345 is about 4607.2057692272. The cubic root of 21226345 is about 276.8800977241.

Adding to 21226345 its reverse (54362212), we get a palindrome (75588557).

The spelling of 21226345 in words is "twenty-one million, two hundred twenty-six thousand, three hundred forty-five".