21121012201121 has 16 divisors (see below), whose sum is σ = 24633008870400. Its totient is φ = 18102187968480.

The previous prime is 21121012201103. The next prime is 21121012201193. The reversal of 21121012201121 is 12110221012112.

It is not a de Polignac number, because 21121012201121 - 2⁴² = 16722965690017 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21121012201121.

It is not an unprimeable number, because it can be changed into a prime (21121012201921) 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, 1442141 + ... + 6657461.

It is an arithmetic number, because the mean of its divisors is an integer number (1539563054400).

Almost surely, 2^{21121012201121} is an apocalyptic number.

It is an amenable number.

21121012201121 is a deficient number, since it is larger than the sum of its proper divisors (3511996669279).

21121012201121 is an equidigital number, since it uses as much as digits as its factorization.

21121012201121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5227149 (or 5227135 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21121012201121 its reverse (12110221012112), we get a palindrome (33231233213233).

The spelling of 21121012201121 in words is "twenty-one trillion, one hundred twenty-one billion, twelve million, two hundred one thousand, one hundred twenty-one".