21064929 has 4 divisors (see below), whose sum is σ = 28086576. Its totient is φ = 14043284.

The previous prime is 21064913. The next prime is 21064937. The reversal of 21064929 is 92946012.

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 21064929 - 2⁴ = 21064913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21064929.

It is not an unprimeable number, because it can be changed into a prime (21060929) 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, 3510819 + ... + 3510824.

It is an arithmetic number, because the mean of its divisors is an integer number (7021644).

Almost surely, 2^21064929 is an apocalyptic number.

It is an amenable number.

21064929 is a deficient number, since it is larger than the sum of its proper divisors (7021647).

21064929 is an equidigital number, since it uses as much as digits as its factorization.

21064929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7021646.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 21064929 is about 4589.6545621648. The cubic root of 21064929 is about 276.1764650750.

The spelling of 21064929 in words is "twenty-one million, sixty-four thousand, nine hundred twenty-nine".