2131430221 has 2 divisors, whose sum is σ = 2131430222. Its totient is φ = 2131430220.

The previous prime is 2131430201. The next prime is 2131430239. The reversal of 2131430221 is 1220341312.

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., 1541426121 + 590004100 = 39261^2 + 24290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2131430221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2131430201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1065715110 + 1065715111.

It is an arithmetic number, because the mean of its divisors is an integer number (1065715111).

Almost surely, 2^2131430221 is an apocalyptic number.

It is an amenable number.

2131430221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2131430221 is an equidigital number, since it uses as much as digits as its factorization.

2131430221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 2131430221 is about 46167.4151431505. The cubic root of 2131430221 is about 1286.9362666807.

Adding to 2131430221 its reverse (1220341312), we get a palindrome (3351771533).

The spelling of 2131430221 in words is "two billion, one hundred thirty-one million, four hundred thirty thousand, two hundred twenty-one".