21313244 has 12 divisors (see below), whose sum is σ = 38501568. Its totient is φ = 10312800.

The previous prime is 21313241. The next prime is 21313247. The reversal of 21313244 is 44231312.

It is an interprime number because it is at equal distance from previous prime (21313241) and next prime (21313247).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21313241) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 85817 + ... + 86064.

It is an arithmetic number, because the mean of its divisors is an integer number (3208464).

Almost surely, 2^21313244 is an apocalyptic number.

It is an amenable number.

21313244 is a deficient number, since it is larger than the sum of its proper divisors (17188324).

21313244 is a wasteful number, since it uses less digits than its factorization.

21313244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171916 (or 171914 counting only the distinct ones).

The product of its digits is 576, while the sum is 20.

The square root of 21313244 is about 4616.6269071693. The cubic root of 21313244 is about 277.2574251130.

Adding to 21313244 its reverse (44231312), we get a palindrome (65544556).

The spelling of 21313244 in words is "twenty-one million, three hundred thirteen thousand, two hundred forty-four".