12131002021 has 4 divisors (see below), whose sum is σ = 12136350700. Its totient is φ = 12125653344.

The previous prime is 12131002007. The next prime is 12131002123. The reversal of 12131002021 is 12020013121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12020013121 = 149 ⋅80671229.

It can be written as a sum of positive squares in 2 ways, for example, as 4591553121 + 7539448900 = 67761^2 + 86830^2 .

It is a cyclic number.

It is not a de Polignac number, because 12131002021 - 2⁷ = 12131001893 is a prime.

It is a super-2 number, since 2×12131002021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12131001992 and 12131002010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12131002321) 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, 2670936 + ... + 2675473.

It is an arithmetic number, because the mean of its divisors is an integer number (3034087675).

Almost surely, 2^12131002021 is an apocalyptic number.

It is an amenable number.

12131002021 is a deficient number, since it is larger than the sum of its proper divisors (5348679).

12131002021 is an equidigital number, since it uses as much as digits as its factorization.

12131002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5348678.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 12131002021 its reverse (12020013121), we get a palindrome (24151015142).

It can be divided in two parts, 1213100 and 2021, that added together give a palindrome (1215121).

The spelling of 12131002021 in words is "twelve billion, one hundred thirty-one million, two thousand, twenty-one".