21026267 has 2 divisors, whose sum is σ = 21026268. Its totient is φ = 21026266.

The previous prime is 21026251. The next prime is 21026287. The reversal of 21026267 is 76262012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21026267 - 2⁴ = 21026251 is a prime.

It is not a weakly prime, because it can be changed into another prime (21026237) by changing a digit.

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 as a sum of consecutive naturals, namely, 10513133 + 10513134.

It is an arithmetic number, because the mean of its divisors is an integer number (10513134).

Almost surely, 2^21026267 is an apocalyptic number.

21026267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21026267 is an equidigital number, since it uses as much as digits as its factorization.

21026267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 21026267 is about 4585.4407639833. The cubic root of 21026267 is about 276.0073993325.

Adding to 21026267 its reverse (76262012), we get a palindrome (97288279).

The spelling of 21026267 in words is "twenty-one million, twenty-six thousand, two hundred sixty-seven".