21311441 has 8 divisors (see below), whose sum is σ = 21552384. Its totient is φ = 21072240.

The previous prime is 21311429. The next prime is 21311443. The reversal of 21311441 is 14411312.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21311441 - 2¹⁰ = 21310417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21311443) 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 7 ways as a sum of consecutive naturals, for example, 50411 + ... + 50831.

It is an arithmetic number, because the mean of its divisors is an integer number (2694048).

Almost surely, 2^21311441 is an apocalyptic number.

It is an amenable number.

21311441 is a deficient number, since it is larger than the sum of its proper divisors (240943).

21311441 is a wasteful number, since it uses less digits than its factorization.

21311441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 871.

The product of its digits is 96, while the sum is 17.

The square root of 21311441 is about 4616.4316305995. The cubic root of 21311441 is about 277.2496066687.

Adding to 21311441 its reverse (14411312), we get a palindrome (35722753).

The spelling of 21311441 in words is "twenty-one million, three hundred eleven thousand, four hundred forty-one".