42581018509 has 2 divisors, whose sum is σ = 42581018510. Its totient is φ = 42581018508.

The previous prime is 42581018497. The next prime is 42581018539. The reversal of 42581018509 is 90581018524.

42581018509 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., 40161362409 + 2419656100 = 200403^2 + 49190^2 .

It is a cyclic number.

It is not a de Polignac number, because 42581018509 - 2²⁵ = 42547464077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42581018539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21290509254 + 21290509255.

It is an arithmetic number, because the mean of its divisors is an integer number (21290509255).

Almost surely, 2^42581018509 is an apocalyptic number.

It is an amenable number.

42581018509 is a deficient number, since it is larger than the sum of its proper divisors (1).

42581018509 is an equidigital number, since it uses as much as digits as its factorization.

42581018509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 115200, while the sum is 43.

The spelling of 42581018509 in words is "forty-two billion, five hundred eighty-one million, eighteen thousand, five hundred nine".