21211121201121 has 20 divisors (see below), whose sum is σ = 33353419954800. Its totient is φ = 13396497599736.

The previous prime is 21211121201057. The next prime is 21211121201143. The reversal of 21211121201121 is 12110212111212.

It is a happy number.

21211121201121 is a `hidden beast` number, since 212 + 11 + 121 + 201 + 121 = 666.

It is not a de Polignac number, because 21211121201121 - 2⁶ = 21211121201057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211121201094 and 21211121201103.

It is not an unprimeable number, because it can be changed into a prime (21211121201191) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6891200931 + ... + 6891204008.

It is an arithmetic number, because the mean of its divisors is an integer number (1667670997740).

Almost surely, 2^{21211121201121} is an apocalyptic number.

It is an amenable number.

21211121201121 is a deficient number, since it is larger than the sum of its proper divisors (12142298753679).

21211121201121 is a wasteful number, since it uses less digits than its factorization.

21211121201121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13782404970 (or 13782404961 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21211121201121 its reverse (12110212111212), we get a palindrome (33321333312333).

It can be divided in two parts, 2121112 and 1201121, that added together give a palindrome (3322233).

The spelling of 21211121201121 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-one million, two hundred one thousand, one hundred twenty-one".