21221001222211 has 16 divisors (see below), whose sum is σ = 25534199968000. Its totient is φ = 17228597457888.

The previous prime is 21221001222191. The next prime is 21221001222229. The reversal of 21221001222211 is 11222210012212.

It is a cyclic number.

It is not a de Polignac number, because 21221001222211 - 2¹¹ = 21221001220163 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221001222271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15516261 + ... + 16828438.

It is an arithmetic number, because the mean of its divisors is an integer number (1595887498000).

Almost surely, 2^{21221001222211} is an apocalyptic number.

21221001222211 is a deficient number, since it is larger than the sum of its proper divisors (4313198745789).

21221001222211 is a wasteful number, since it uses less digits than its factorization.

21221001222211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32349658.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21221001222211 its reverse (11222210012212), we get a palindrome (32443211234423).

The spelling of 21221001222211 in words is "twenty-one trillion, two hundred twenty-one billion, one million, two hundred twenty-two thousand, two hundred eleven".