21001122111201 has 32 divisors (see below), whose sum is σ = 29594883632640. Its totient is φ = 13210108539264.

The previous prime is 21001122111139. The next prime is 21001122111209. The reversal of 21001122111201 is 10211122110012.

It is a happy number.

It is not a de Polignac number, because 21001122111201 - 2¹¹ = 21001122109153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001122111209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20243010 + ... + 21255156.

It is an arithmetic number, because the mean of its divisors is an integer number (924840113520).

Almost surely, 2^{21001122111201} is an apocalyptic number.

It is an amenable number.

21001122111201 is a deficient number, since it is larger than the sum of its proper divisors (8593761521439).

21001122111201 is a wasteful number, since it uses less digits than its factorization.

21001122111201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013645.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21001122111201 its reverse (10211122110012), we get a palindrome (31212244221213).

The spelling of 21001122111201 in words is "twenty-one trillion, one billion, one hundred twenty-two million, one hundred eleven thousand, two hundred one".