21611344 has 10 divisors (see below), whose sum is σ = 41872010. Its totient is φ = 10805664.

The previous prime is 21611323. The next prime is 21611347. The reversal of 21611344 is 44311612.

It can be written as a sum of positive squares in only one way, i.e., 13838400 + 7772944 = 3720^2 + 2788^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21611347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 675339 + ... + 675370.

It is an arithmetic number, because the mean of its divisors is an integer number (4187201).

Almost surely, 2^21611344 is an apocalyptic number.

It is an amenable number.

21611344 is a deficient number, since it is larger than the sum of its proper divisors (20260666).

21611344 is a wasteful number, since it uses less digits than its factorization.

21611344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1350717 (or 1350711 counting only the distinct ones).

The product of its digits is 576, while the sum is 22.

The square root of 21611344 is about 4648.8002753399. The cubic root of 21611344 is about 278.5440753581.

Adding to 21611344 its reverse (44311612), we get a palindrome (65922956).

The spelling of 21611344 in words is "twenty-one million, six hundred eleven thousand, three hundred forty-four".