12021121021 has 16 divisors (see below), whose sum is σ = 14797801984. Its totient is φ = 9509560704.

The previous prime is 12021121019. The next prime is 12021121027. The reversal of 12021121021 is 12012112021.

It is not a de Polignac number, because 12021121021 - 2¹ = 12021121019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 12021120992 and 12021121010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12021121027) 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, 1005340 + ... + 1017226.

It is an arithmetic number, because the mean of its divisors is an integer number (924862624).

Almost surely, 2^12021121021 is an apocalyptic number.

It is an amenable number.

12021121021 is a deficient number, since it is larger than the sum of its proper divisors (2776680963).

12021121021 is a wasteful number, since it uses less digits than its factorization.

12021121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23020.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 12021121021 its reverse (12012112021), we get a palindrome (24033233042).

The spelling of 12021121021 in words is "twelve billion, twenty-one million, one hundred twenty-one thousand, twenty-one".