805243342509 has 24 divisors (see below), whose sum is σ = 1173918826080. Its totient is φ = 531850097952.

The previous prime is 805243342493. The next prime is 805243342511. The reversal of 805243342509 is 905243342508.

805243342509 is a `hidden beast` number, since 8 + 0 + 524 + 33 + 42 + 50 + 9 = 666.

It is not a de Polignac number, because 805243342509 - 2⁴ = 805243342493 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805243342109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11229082 + ... + 11300564.

It is an arithmetic number, because the mean of its divisors is an integer number (48913284420).

Almost surely, 2^805243342509 is an apocalyptic number.

It is an amenable number.

805243342509 is a deficient number, since it is larger than the sum of its proper divisors (368675483571).

805243342509 is a wasteful number, since it uses less digits than its factorization.

805243342509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83081 (or 83078 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 45.

Subtracting 805243342509 from its reverse (905243342508), we obtain a palindrome (99999999999).

The spelling of 805243342509 in words is "eight hundred five billion, two hundred forty-three million, three hundred forty-two thousand, five hundred nine".