845424509 has 2 divisors, whose sum is σ = 845424510. Its totient is φ = 845424508.

The previous prime is 845424497. The next prime is 845424523. The reversal of 845424509 is 905424548.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 793267225 + 52157284 = 28165^2 + 7222^2 .

It is a cyclic number.

It is not a de Polignac number, because 845424509 - 2⁴ = 845424493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (845424599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422712254 + 422712255.

It is an arithmetic number, because the mean of its divisors is an integer number (422712255).

Almost surely, 2^845424509 is an apocalyptic number.

It is an amenable number.

845424509 is a deficient number, since it is larger than the sum of its proper divisors (1).

845424509 is an equidigital number, since it uses as much as digits as its factorization.

845424509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 230400, while the sum is 41.

The square root of 845424509 is about 29076.1845674428. The cubic root of 845424509 is about 945.5654851997.

The spelling of 845424509 in words is "eight hundred forty-five million, four hundred twenty-four thousand, five hundred nine".