21366907 has 2 divisors, whose sum is σ = 21366908. Its totient is φ = 21366906.

The previous prime is 21366901. The next prime is 21366911. The reversal of 21366907 is 70966312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21366907 is a prime.

It is not a weakly prime, because it can be changed into another prime (21366901) 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, 10683453 + 10683454.

It is an arithmetic number, because the mean of its divisors is an integer number (10683454).

Almost surely, 2^21366907 is an apocalyptic number.

21366907 is a deficient number, since it is larger than the sum of its proper divisors (1).

21366907 is an equidigital number, since it uses as much as digits as its factorization.

21366907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 21366907 is about 4622.4351807245. The cubic root of 21366907 is about 277.4899252355.

The spelling of 21366907 in words is "twenty-one million, three hundred sixty-six thousand, nine hundred seven".