21101121002121 has 16 divisors (see below), whose sum is σ = 28255420372608. Its totient is φ = 14007133728000.

The previous prime is 21101121002029. The next prime is 21101121002123. The reversal of 21101121002121 is 12120012110112.

It is a happy number.

It is not a de Polignac number, because 21101121002121 - 2¹⁵ = 21101120969353 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21101121002121.

It is not an unprimeable number, because it can be changed into a prime (21101121002123) 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, 3329635 + ... + 7299911.

It is an arithmetic number, because the mean of its divisors is an integer number (1765963773288).

Almost surely, 2^{21101121002121} is an apocalyptic number.

It is an amenable number.

21101121002121 is a deficient number, since it is larger than the sum of its proper divisors (7154299370487).

21101121002121 is a wasteful number, since it uses less digits than its factorization.

21101121002121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3977872.

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

Adding to 21101121002121 its reverse (12120012110112), we get a palindrome (33221133112233).

The spelling of 21101121002121 in words is "twenty-one trillion, one hundred one billion, one hundred twenty-one million, two thousand, one hundred twenty-one".