21220441 has 8 divisors (see below), whose sum is σ = 23495904. Its totient is φ = 19002720.

The previous prime is 21220429. The next prime is 21220477. The reversal of 21220441 is 14402212.

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

It is not a de Polignac number, because 21220441 - 2⁷ = 21220313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221441) 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, 13660 + ... + 15133.

It is an arithmetic number, because the mean of its divisors is an integer number (2936988).

Almost surely, 2^21220441 is an apocalyptic number.

It is an amenable number.

21220441 is a deficient number, since it is larger than the sum of its proper divisors (2275463).

21220441 is a wasteful number, since it uses less digits than its factorization.

21220441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28871.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 21220441 is about 4606.5649892300. The cubic root of 21220441 is about 276.8544244129.

Adding to 21220441 its reverse (14402212), we get a palindrome (35622653).

The spelling of 21220441 in words is "twenty-one million, two hundred twenty thousand, four hundred forty-one".