21211210001121 has 16 divisors (see below), whose sum is σ = 32322514560000. Its totient is φ = 12120439898448.

The previous prime is 21211210001077. The next prime is 21211210001161. The reversal of 21211210001121 is 12110001211212.

It is a happy number.

It is not a de Polignac number, because 21211210001121 - 2²⁶ = 21211142892257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21211210001121.

It is not an unprimeable number, because it can be changed into a prime (21211210001161) 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, 9442021 + ... + 11470578.

It is an arithmetic number, because the mean of its divisors is an integer number (2020157160000).

Almost surely, 2^{21211210001121} is an apocalyptic number.

21211210001121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21211210001121 is a deficient number, since it is larger than the sum of its proper divisors (11111304558879).

21211210001121 is a wasteful number, since it uses less digits than its factorization.

21211210001121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20960908.

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

Adding to 21211210001121 its reverse (12110001211212), we get a palindrome (33321211212333).

The spelling of 21211210001121 in words is "twenty-one trillion, two hundred eleven billion, two hundred ten million, one thousand, one hundred twenty-one".