21044855 has 8 divisors (see below), whose sum is σ = 27196512. Its totient is φ = 15540768.

The previous prime is 21044833. The next prime is 21044873. The reversal of 21044855 is 55844012.

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

It is a cyclic number.

It is not a de Polignac number, because 21044855 - 2⁶ = 21044791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161819 + ... + 161948.

It is an arithmetic number, because the mean of its divisors is an integer number (3399564).

Almost surely, 2^21044855 is an apocalyptic number.

21044855 is a deficient number, since it is larger than the sum of its proper divisors (6151657).

21044855 is a wasteful number, since it uses less digits than its factorization.

21044855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323785.

The product of its (nonzero) digits is 6400, while the sum is 29.

The square root of 21044855 is about 4587.4671660950. The cubic root of 21044855 is about 276.0887089702.

Adding to 21044855 its reverse (55844012), we get a palindrome (76888867).

The spelling of 21044855 in words is "twenty-one million, forty-four thousand, eight hundred fifty-five".