43531391789 has 2 divisors, whose sum is σ = 43531391790. Its totient is φ = 43531391788.

The previous prime is 43531391719. The next prime is 43531391791. The reversal of 43531391789 is 98719313534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34460353225 + 9071038564 = 185635^2 + 95242^2 .

It is a cyclic number.

It is not a de Polignac number, because 43531391789 - 2²⁸ = 43262956333 is a prime.

Together with 43531391791, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 43531391789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43531391719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21765695894 + 21765695895.

It is an arithmetic number, because the mean of its divisors is an integer number (21765695895).

Almost surely, 2^43531391789 is an apocalyptic number.

It is an amenable number.

43531391789 is a deficient number, since it is larger than the sum of its proper divisors (1).

43531391789 is an equidigital number, since it uses as much as digits as its factorization.

43531391789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2449440, while the sum is 53.

The spelling of 43531391789 in words is "forty-three billion, five hundred thirty-one million, three hundred ninety-one thousand, seven hundred eighty-nine".