21052267 has 2 divisors, whose sum is σ = 21052268. Its totient is φ = 21052266.

The previous prime is 21052261. The next prime is 21052279. The reversal of 21052267 is 76225012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21052267 is a prime.

It is not a weakly prime, because it can be changed into another prime (21052261) 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, 10526133 + 10526134.

It is an arithmetic number, because the mean of its divisors is an integer number (10526134).

Almost surely, 2^21052267 is an apocalyptic number.

21052267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21052267 is an equidigital number, since it uses as much as digits as its factorization.

21052267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21052267 is about 4588.2749481695. The cubic root of 21052267 is about 276.1211179891.

Adding to 21052267 its reverse (76225012), we get a palindrome (97277279).

The spelling of 21052267 in words is "twenty-one million, fifty-two thousand, two hundred sixty-seven".