21344672 has 12 divisors (see below), whose sum is σ = 42022386. Its totient is φ = 10672320.

The previous prime is 21344669. The next prime is 21344677. The reversal of 21344672 is 27644312.

It can be written as a sum of positive squares in only one way, i.e., 17673616 + 3671056 = 4204^2 + 1916^2 .

It is not an unprimeable number, because it can be changed into a prime (21344677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333479 + ... + 333542.

Almost surely, 2^21344672 is an apocalyptic number.

It is an amenable number.

21344672 is a deficient number, since it is larger than the sum of its proper divisors (20677714).

21344672 is an equidigital number, since it uses as much as digits as its factorization.

21344672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667031 (or 667023 counting only the distinct ones).

The product of its digits is 8064, while the sum is 29.

The square root of 21344672 is about 4620.0294371357. The cubic root of 21344672 is about 277.3936372398.

Adding to 21344672 its reverse (27644312), we get a palindrome (48988984).

The spelling of 21344672 in words is "twenty-one million, three hundred forty-four thousand, six hundred seventy-two".