2131002221 has 2 divisors, whose sum is σ = 2131002222. Its totient is φ = 2131002220.

The previous prime is 2131002199. The next prime is 2131002227. The reversal of 2131002221 is 1222001312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2105892100 + 25110121 = 45890^2 + 5011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2131002221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2131002196 and 2131002205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2131002227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1065501110 + 1065501111.

It is an arithmetic number, because the mean of its divisors is an integer number (1065501111).

Almost surely, 2^2131002221 is an apocalyptic number.

It is an amenable number.

2131002221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2131002221 is an equidigital number, since it uses as much as digits as its factorization.

2131002221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 2131002221 is about 46162.7796065185. The cubic root of 2131002221 is about 1286.8501202067.

Adding to 2131002221 its reverse (1222001312), we get a palindrome (3353003533).

Subtracting from 2131002221 its reverse (1222001312), we obtain a palindrome (909000909).

The spelling of 2131002221 in words is "two billion, one hundred thirty-one million, two thousand, two hundred twenty-one".