21112201122221 has 16 divisors (see below), whose sum is σ = 24379767149760. Its totient is φ = 18100130133120.

The previous prime is 21112201122209. The next prime is 21112201122227. The reversal of 21112201122221 is 12222110221112.

It is a cyclic number.

It is not a de Polignac number, because 21112201122221 - 2⁶ = 21112201122157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21112201122193 and 21112201122202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112201122227) 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, 769549640 + ... + 769577073.

It is an arithmetic number, because the mean of its divisors is an integer number (1523735446860).

Almost surely, 2^{21112201122221} is an apocalyptic number.

It is an amenable number.

21112201122221 is a deficient number, since it is larger than the sum of its proper divisors (3267566027539).

21112201122221 is a wasteful number, since it uses less digits than its factorization.

21112201122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539126796.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21112201122221 its reverse (12222110221112), we get a palindrome (33334311343333).

The spelling of 21112201122221 in words is "twenty-one trillion, one hundred twelve billion, two hundred one million, one hundred twenty-two thousand, two hundred twenty-one".