21220100221 has 8 divisors (see below), whose sum is σ = 21528460800. Its totient is φ = 20912003280.

The previous prime is 21220100207. The next prime is 21220100227. The reversal of 21220100221 is 12200102212.

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 21220100221 - 2⁵ = 21220100189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220100227) 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, 99220 + ... + 228658.

It is an arithmetic number, because the mean of its divisors is an integer number (2691057600).

Almost surely, 2^21220100221 is an apocalyptic number.

It is an amenable number.

21220100221 is a deficient number, since it is larger than the sum of its proper divisors (308360579).

21220100221 is a wasteful number, since it uses less digits than its factorization.

21220100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131819.

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

Adding to 21220100221 its reverse (12200102212), we get a palindrome (33420202433).

The spelling of 21220100221 in words is "twenty-one billion, two hundred twenty million, one hundred thousand, two hundred twenty-one".