21107344 has 10 divisors (see below), whose sum is σ = 40895510. Its totient is φ = 10553664.

The previous prime is 21107341. The next prime is 21107351. The reversal of 21107344 is 44370112.

It can be written as a sum of positive squares in only one way, i.e., 21049744 + 57600 = 4588^2 + 240^2 .

It is not an unprimeable number, because it can be changed into a prime (21107341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 659589 + ... + 659620.

It is an arithmetic number, because the mean of its divisors is an integer number (4089551).

Almost surely, 2^21107344 is an apocalyptic number.

It is an amenable number.

21107344 is a deficient number, since it is larger than the sum of its proper divisors (19788166).

21107344 is a wasteful number, since it uses less digits than its factorization.

21107344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1319217 (or 1319211 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21107344 is about 4594.2729566276. The cubic root of 21107344 is about 276.3617045844.

Adding to 21107344 its reverse (44370112), we get a palindrome (65477456).

The spelling of 21107344 in words is "twenty-one million, one hundred seven thousand, three hundred forty-four".