21044113 has 6 divisors (see below), whose sum is σ = 22355126. Its totient is φ = 19805952.

The previous prime is 21044081. The next prime is 21044117. The reversal of 21044113 is 31144012.

It can be written as a sum of positive squares in 3 ways, for example, as 8427409 + 12616704 = 2903^2 + 3552^2 .

It is not a de Polignac number, because 21044113 - 2⁵ = 21044081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21044117) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36120 + ... + 36697.

Almost surely, 2^21044113 is an apocalyptic number.

It is an amenable number.

21044113 is a deficient number, since it is larger than the sum of its proper divisors (1311013).

21044113 is an equidigital number, since it uses as much as digits as its factorization.

21044113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72851 (or 72834 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 21044113 is about 4587.3862928687. The cubic root of 21044113 is about 276.0854641513.

Adding to 21044113 its reverse (31144012), we get a palindrome (52188125).

The spelling of 21044113 in words is "twenty-one million, forty-four thousand, one hundred thirteen".