21064461 has 8 divisors (see below), whose sum is σ = 30639264. Its totient is φ = 12766320.

The previous prime is 21064363. The next prime is 21064471. The reversal of 21064461 is 16446012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21064461 - 2¹¹ = 21062413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064471) 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, 319126 + ... + 319191.

It is an arithmetic number, because the mean of its divisors is an integer number (3829908).

Almost surely, 2^21064461 is an apocalyptic number.

It is an amenable number.

21064461 is a deficient number, since it is larger than the sum of its proper divisors (9574803).

21064461 is a wasteful number, since it uses less digits than its factorization.

21064461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 638331.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21064461 is about 4589.6035776524. The cubic root of 21064461 is about 276.1744197869.

The spelling of 21064461 in words is "twenty-one million, sixty-four thousand, four hundred sixty-one".