2130531581 has 2 divisors, whose sum is σ = 2130531582. Its totient is φ = 2130531580.

The previous prime is 2130531563. The next prime is 2130531583. The reversal of 2130531581 is 1851350312.

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., 1900524025 + 230007556 = 43595^2 + 15166^2 .

It is a cyclic number.

It is not a de Polignac number, because 2130531581 - 2⁶ = 2130531517 is a prime.

It is a super-2 number, since 2×2130531581² = 9078329635276719122, which contains 22 as substring.

Together with 2130531583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2130531583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1065265790 + 1065265791.

It is an arithmetic number, because the mean of its divisors is an integer number (1065265791).

Almost surely, 2^2130531581 is an apocalyptic number.

It is an amenable number.

2130531581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2130531581 is an equidigital number, since it uses as much as digits as its factorization.

2130531581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 2130531581 is about 46157.6817117151. The cubic root of 2130531581 is about 1286.7553779729.

Adding to 2130531581 its reverse (1851350312), we get a palindrome (3981881893).

The spelling of 2130531581 in words is "two billion, one hundred thirty million, five hundred thirty-one thousand, five hundred eighty-one".