2143312981 has 2 divisors, whose sum is σ = 2143312982. Its totient is φ = 2143312980.

The previous prime is 2143312973. The next prime is 2143313033. The reversal of 2143312981 is 1892133412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1886512356 + 256800625 = 43434^2 + 16025^2 .

It is a cyclic number.

It is not a de Polignac number, because 2143312981 - 2³ = 2143312973 is a prime.

It is a super-2 number, since 2×2143312981² = 9187581069046212722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2143312921) 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, 1071656490 + 1071656491.

It is an arithmetic number, because the mean of its divisors is an integer number (1071656491).

Almost surely, 2^2143312981 is an apocalyptic number.

It is an amenable number.

2143312981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2143312981 is an equidigital number, since it uses as much as digits as its factorization.

2143312981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 34.

The square root of 2143312981 is about 46295.9283414859. The cubic root of 2143312981 is about 1289.3233999703.

The spelling of 2143312981 in words is "two billion, one hundred forty-three million, three hundred twelve thousand, nine hundred eighty-one".