21011344 has 20 divisors (see below), whose sum is σ = 40885900. Its totient is φ = 10460160.

The previous prime is 21011327. The next prime is 21011357. The reversal of 21011344 is 44311012.

It can be written as a sum of positive squares in 2 ways, for example, as 8479744 + 12531600 = 2912^2 + 3540^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1132 + ... + 6580.

It is an arithmetic number, because the mean of its divisors is an integer number (2044295).

Almost surely, 2^21011344 is an apocalyptic number.

It is an amenable number.

21011344 is a deficient number, since it is larger than the sum of its proper divisors (19874556).

21011344 is a wasteful number, since it uses less digits than its factorization.

21011344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5698 (or 5692 counting only the distinct ones).

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

The square root of 21011344 is about 4583.8132597216. The cubic root of 21011344 is about 275.9420868477.

Adding to 21011344 its reverse (44311012), we get a palindrome (65322356).

The spelling of 21011344 in words is "twenty-one million, eleven thousand, three hundred forty-four".