21058663 has 2 divisors, whose sum is σ = 21058664. Its totient is φ = 21058662.

The previous prime is 21058657. The next prime is 21058711. The reversal of 21058663 is 36685012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21058663 - 2⁹ = 21058151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21058633) 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, 10529331 + 10529332.

It is an arithmetic number, because the mean of its divisors is an integer number (10529332).

Almost surely, 2^21058663 is an apocalyptic number.

21058663 is a deficient number, since it is larger than the sum of its proper divisors (1).

21058663 is an equidigital number, since it uses as much as digits as its factorization.

21058663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 21058663 is about 4588.9718892144. The cubic root of 21058663 is about 276.1490784276.

The spelling of 21058663 in words is "twenty-one million, fifty-eight thousand, six hundred sixty-three".