21344064 has 56 divisors (see below), whose sum is σ = 64544448. Its totient is φ = 6097920.

The previous prime is 21344051. The next prime is 21344077. The reversal of 21344064 is 46044312.

It is an interprime number because it is at equal distance from previous prime (21344051) and next prime (21344077).

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

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, 6597 + ... + 9284.

Almost surely, 2^21344064 is an apocalyptic number.

21344064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21344064 is an abundant number, since it is smaller than the sum of its proper divisors (43200384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21344064 is a wasteful number, since it uses less digits than its factorization.

21344064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15903 (or 15893 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 21344064 is about 4619.9636362205. The cubic root of 21344064 is about 277.3910033752.

Adding to 21344064 its reverse (46044312), we get a palindrome (67388376).

It can be divided in two parts, 21 and 344064, that multiplied together give a square (7225344 = 2688²).

The spelling of 21344064 in words is "twenty-one million, three hundred forty-four thousand, sixty-four".