21027064 has 8 divisors (see below), whose sum is σ = 39425760. Its totient is φ = 10513528.

The previous prime is 21027049. The next prime is 21027067. The reversal of 21027064 is 46072012.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21027067) 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 as a sum of consecutive naturals, namely, 1314184 + ... + 1314199.

It is an arithmetic number, because the mean of its divisors is an integer number (4928220).

Almost surely, 2^21027064 is an apocalyptic number.

It is an amenable number.

21027064 is a deficient number, since it is larger than the sum of its proper divisors (18398696).

21027064 is a wasteful number, since it uses less digits than its factorization.

21027064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2628389 (or 2628385 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21027064 is about 4585.5276686549. The cubic root of 21027064 is about 276.0108866391.

Adding to 21027064 its reverse (46072012), we get a palindrome (67099076).

The spelling of 21027064 in words is "twenty-one million, twenty-seven thousand, sixty-four".