21112207 has 2 divisors, whose sum is σ = 21112208. Its totient is φ = 21112206.

The previous prime is 21112199. The next prime is 21112241. The reversal of 21112207 is 70221112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21112207 - 2³ = 21112199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21112907) 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, 10556103 + 10556104.

It is an arithmetic number, because the mean of its divisors is an integer number (10556104).

Almost surely, 2^21112207 is an apocalyptic number.

21112207 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112207 is an equidigital number, since it uses as much as digits as its factorization.

21112207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 21112207 is about 4594.8021720200. The cubic root of 21112207 is about 276.3829269572.

Adding to 21112207 its reverse (70221112), we get a palindrome (91333319).

The spelling of 21112207 in words is "twenty-one million, one hundred twelve thousand, two hundred seven".