21220010221 has 8 divisors (see below), whose sum is σ = 21266451360. Its totient is φ = 21173613552.

The previous prime is 21220010177. The next prime is 21220010233. The reversal of 21220010221 is 12201002212.

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 21220010221 - 2⁹ = 21220009709 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 (21220010261) 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, 1052986 + ... + 1072948.

It is an arithmetic number, because the mean of its divisors is an integer number (2658306420).

Almost surely, 2^21220010221 is an apocalyptic number.

It is an amenable number.

21220010221 is a deficient number, since it is larger than the sum of its proper divisors (46441139).

21220010221 is a wasteful number, since it uses less digits than its factorization.

21220010221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22235.

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

Adding to 21220010221 its reverse (12201002212), we get a palindrome (33421012433).

The spelling of 21220010221 in words is "twenty-one billion, two hundred twenty million, ten thousand, two hundred twenty-one".