21220221001 has 8 divisors (see below), whose sum is σ = 24391865664. Its totient is φ = 18083622480.

The previous prime is 21220220941. The next prime is 21220221031. The reversal of 21220221001 is 10012202212.

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 21220221001 - 2⁷ = 21220220873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21220221031) 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, 8760235 + ... + 8762656.

It is an arithmetic number, because the mean of its divisors is an integer number (3048983208).

Almost surely, 2^21220221001 is an apocalyptic number.

It is an amenable number.

21220221001 is a deficient number, since it is larger than the sum of its proper divisors (3171644663).

21220221001 is a wasteful number, since it uses less digits than its factorization.

21220221001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17523071.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21220221001 its reverse (10012202212), we get a palindrome (31232423213).

The spelling of 21220221001 in words is "twenty-one billion, two hundred twenty million, two hundred twenty-one thousand, one".