21122001011121 has 24 divisors (see below), whose sum is σ = 29920710227424. Its totient is φ = 13251263316480.

The previous prime is 21122001011099. The next prime is 21122001011197. The reversal of 21122001011121 is 12111010022112.

It is a happy number.

It is not a de Polignac number, because 21122001011121 - 2²¹ = 21121998913969 is a prime.

It is a super-2 number, since 2×21122001011121² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21122001011121.

It is not an unprimeable number, because it can be changed into a prime (21122001011521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4944346 + ... + 8166428.

It is an arithmetic number, because the mean of its divisors is an integer number (1246696259476).

Almost surely, 2^{21122001011121} is an apocalyptic number.

It is an amenable number.

21122001011121 is a deficient number, since it is larger than the sum of its proper divisors (8798709216303).

21122001011121 is a wasteful number, since it uses less digits than its factorization.

21122001011121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3229681 (or 3229664 counting only the distinct ones).

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

Adding to 21122001011121 its reverse (12111010022112), we get a palindrome (33233011033233).

The spelling of 21122001011121 in words is "twenty-one trillion, one hundred twenty-two billion, one million, eleven thousand, one hundred twenty-one".