21063213 has 8 divisors (see below), whose sum is σ = 31204800. Its totient is φ = 14042124.

The previous prime is 21063199. The next prime is 21063223. The reversal of 21063213 is 31236012.

21063213 is a `hidden beast` number, since 21 + 0 + 632 + 13 = 666.

It is not a de Polignac number, because 21063213 - 2⁵ = 21063181 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21063223) 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 in 7 ways as a sum of consecutive naturals, for example, 390033 + ... + 390086.

It is an arithmetic number, because the mean of its divisors is an integer number (3900600).

Almost surely, 2^21063213 is an apocalyptic number.

It is an amenable number.

21063213 is a deficient number, since it is larger than the sum of its proper divisors (10141587).

21063213 is an equidigital number, since it uses as much as digits as its factorization.

21063213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780128 (or 780122 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 21063213 is about 4589.4676161838. The cubic root of 21063213 is about 276.1689655373.

Adding to 21063213 its reverse (31236012), we get a palindrome (52299225).

The spelling of 21063213 in words is "twenty-one million, sixty-three thousand, two hundred thirteen".