21226023 has 64 divisors (see below), whose sum is σ = 39674880. Its totient is φ = 10917504.

The previous prime is 21226019. The next prime is 21226027. The reversal of 21226023 is 32062212.

It is an interprime number because it is at equal distance from previous prime (21226019) and next prime (21226027).

It is not a de Polignac number, because 21226023 - 2² = 21226019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21225987 and 21226005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21226027) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 130140 + ... + 130302.

It is an arithmetic number, because the mean of its divisors is an integer number (619920).

Almost surely, 2^21226023 is an apocalyptic number.

21226023 is a deficient number, since it is larger than the sum of its proper divisors (18448857).

21226023 is a wasteful number, since it uses less digits than its factorization.

21226023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245 (or 239 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 21226023 is about 4607.1708238354. The cubic root of 21226023 is about 276.8786976425.

Adding to 21226023 its reverse (32062212), we get a palindrome (53288235).

The spelling of 21226023 in words is "twenty-one million, two hundred twenty-six thousand, twenty-three".