1143439981 has 2 divisors, whose sum is σ = 1143439982. Its totient is φ = 1143439980.

The previous prime is 1143439951. The next prime is 1143440003. The reversal of 1143439981 is 1899343411.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 903964356 + 239475625 = 30066^2 + 15475^2 .

It is a cyclic number.

It is not a de Polignac number, because 1143439981 - 2⁷ = 1143439853 is a prime.

It is a super-2 number, since 2×1143439981² = 2614909980298560722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1143439951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 571719990 + 571719991.

It is an arithmetic number, because the mean of its divisors is an integer number (571719991).

Almost surely, 2^1143439981 is an apocalyptic number.

It is an amenable number.

1143439981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1143439981 is an equidigital number, since it uses as much as digits as its factorization.

1143439981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 1143439981 is about 33814.7893827538. The cubic root of 1143439981 is about 1045.6936188566.

It can be divided in two parts, 11434 and 39981, that added together give a palindrome (51415).

The spelling of 1143439981 in words is "one billion, one hundred forty-three million, four hundred thirty-nine thousand, nine hundred eighty-one".