21211044 has 24 divisors (see below), whose sum is σ = 49828800. Its totient is φ = 7022304.

The previous prime is 21211039. The next prime is 21211079. The reversal of 21211044 is 44011212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4144 + ... + 7719.

It is an arithmetic number, because the mean of its divisors is an integer number (2076200).

Almost surely, 2^21211044 is an apocalyptic number.

It is an amenable number.

21211044 is an abundant number, since it is smaller than the sum of its proper divisors (28617756).

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

21211044 is a wasteful number, since it uses less digits than its factorization.

21211044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12019 (or 12017 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 21211044 is about 4605.5449188994. The cubic root of 21211044 is about 276.8135521058.

Adding to 21211044 its reverse (44011212), we get a palindrome (65222256).

The spelling of 21211044 in words is "twenty-one million, two hundred eleven thousand, forty-four".