21064269 has 4 divisors (see below), whose sum is σ = 28085696. Its totient is φ = 14042844.

The previous prime is 21064261. The next prime is 21064271. The reversal of 21064269 is 96246012.

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 not a de Polignac number, because 21064269 - 2³ = 21064261 is a prime.

It is a super-3 number, since 3×21064269³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064261) 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, 3510709 + ... + 3510714.

It is an arithmetic number, because the mean of its divisors is an integer number (7021424).

Almost surely, 2^21064269 is an apocalyptic number.

It is an amenable number.

21064269 is a deficient number, since it is larger than the sum of its proper divisors (7021427).

21064269 is an equidigital number, since it uses as much as digits as its factorization.

21064269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7021426.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 21064269 is about 4589.5826607656. The cubic root of 21064269 is about 276.1735806856.

The spelling of 21064269 in words is "twenty-one million, sixty-four thousand, two hundred sixty-nine".