21121441 has 8 divisors (see below), whose sum is σ = 23115168. Its totient is φ = 19140000.

The previous prime is 21121417. The next prime is 21121453. The reversal of 21121441 is 14412112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21121441 - 2⁹ = 21120929 is a prime.

It is a super-2 number, since 2×21121441² = 892230539832962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 741 + ... + 6541.

It is an arithmetic number, because the mean of its divisors is an integer number (2889396).

Almost surely, 2^21121441 is an apocalyptic number.

It is an amenable number.

21121441 is a deficient number, since it is larger than the sum of its proper divisors (1993727).

21121441 is a wasteful number, since it uses less digits than its factorization.

21121441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6143.

The product of its digits is 64, while the sum is 16.

The square root of 21121441 is about 4595.8068932452. The cubic root of 21121441 is about 276.4232156231.

Adding to 21121441 its reverse (14412112), we get a palindrome (35533553).

It can be divided in two parts, 2112 and 1441, that added together give a palindrome (3553).

The spelling of 21121441 in words is "twenty-one million, one hundred twenty-one thousand, four hundred forty-one".