21707267 has 2 divisors, whose sum is σ = 21707268. Its totient is φ = 21707266.

The previous prime is 21707261. The next prime is 21707281. The reversal of 21707267 is 76270712.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21707267 - 2⁴ = 21707251 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21707261) 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 as a sum of consecutive naturals, namely, 10853633 + 10853634.

It is an arithmetic number, because the mean of its divisors is an integer number (10853634).

Almost surely, 2^21707267 is an apocalyptic number.

21707267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21707267 is an equidigital number, since it uses as much as digits as its factorization.

21707267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8232, while the sum is 32.

The square root of 21707267 is about 4659.1058154972. The cubic root of 21707267 is about 278.9555776022.

Adding to 21707267 its reverse (76270712), we get a palindrome (97977979).

The spelling of 21707267 in words is "twenty-one million, seven hundred seven thousand, two hundred sixty-seven".