12120221021 has 4 divisors (see below), whose sum is σ = 12378098112. Its totient is φ = 11862343932.

The previous prime is 12120220993. The next prime is 12120221039. The reversal of 12120221021 is 12012202121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12012202121 = 31 ⋅387490391.

It is a cyclic number.

It is not a de Polignac number, because 12120221021 - 2¹⁰ = 12120219997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12120220987 and 12120221005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12120221221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128938475 + ... + 128938568.

It is an arithmetic number, because the mean of its divisors is an integer number (3094524528).

Almost surely, 2^12120221021 is an apocalyptic number.

It is an amenable number.

12120221021 is a deficient number, since it is larger than the sum of its proper divisors (257877091).

12120221021 is an equidigital number, since it uses as much as digits as its factorization.

12120221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257877090.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 12120221021 its reverse (12012202121), we get a palindrome (24132423142).

The spelling of 12120221021 in words is "twelve billion, one hundred twenty million, two hundred twenty-one thousand, twenty-one".