21064633 has 4 divisors (see below), whose sum is σ = 21269248. Its totient is φ = 20860020.

The previous prime is 21064627. The next prime is 21064679. The reversal of 21064633 is 33646012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21064633 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21064598 and 21064607.

It is not an unprimeable number, because it can be changed into a prime (21064133) 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 in 3 ways as a sum of consecutive naturals, for example, 102153 + ... + 102358.

It is an arithmetic number, because the mean of its divisors is an integer number (5317312).

Almost surely, 2^21064633 is an apocalyptic number.

It is an amenable number.

21064633 is a deficient number, since it is larger than the sum of its proper divisors (204615).

21064633 is a wasteful number, since it uses less digits than its factorization.

21064633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204614.

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 21064633 is about 4589.6223156160. The cubic root of 21064633 is about 276.1751714775.

The spelling of 21064633 in words is "twenty-one million, sixty-four thousand, six hundred thirty-three".