21064733 has 4 divisors (see below), whose sum is σ = 21379200. Its totient is φ = 20750268.

The previous prime is 21064723. The next prime is 21064753. The reversal of 21064733 is 33746012.

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 not a de Polignac number, because 21064733 - 2¹⁶ = 20999197 is a prime.

It is a super-2 number, since 2×21064733² = 887445952722578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064723) 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 3 ways as a sum of consecutive naturals, for example, 157133 + ... + 157266.

It is an arithmetic number, because the mean of its divisors is an integer number (5344800).

Almost surely, 2^21064733 is an apocalyptic number.

It is an amenable number.

21064733 is a deficient number, since it is larger than the sum of its proper divisors (314467).

21064733 is an equidigital number, since it uses as much as digits as its factorization.

21064733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314466.

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 21064733 is about 4589.6332097456. The cubic root of 21064733 is about 276.1756085050.

The spelling of 21064733 in words is "twenty-one million, sixty-four thousand, seven hundred thirty-three".