43420923509 has 2 divisors, whose sum is σ = 43420923510. Its totient is φ = 43420923508.

The previous prime is 43420923499. The next prime is 43420923529. The reversal of 43420923509 is 90532902434.

43420923509 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42180122884 + 1240800625 = 205378^2 + 35225^2 .

It is a cyclic number.

It is not a de Polignac number, because 43420923509 - 2⁴ = 43420923493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43420923529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21710461754 + 21710461755.

It is an arithmetic number, because the mean of its divisors is an integer number (21710461755).

Almost surely, 2^43420923509 is an apocalyptic number.

It is an amenable number.

43420923509 is a deficient number, since it is larger than the sum of its proper divisors (1).

43420923509 is an equidigital number, since it uses as much as digits as its factorization.

43420923509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 233280, while the sum is 41.

The spelling of 43420923509 in words is "forty-three billion, four hundred twenty million, nine hundred twenty-three thousand, five hundred nine".