1818257009 has 2 divisors, whose sum is σ = 1818257010. Its totient is φ = 1818257008.

The previous prime is 1818256939. The next prime is 1818257011. The reversal of 1818257009 is 9007528181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1812630625 + 5626384 = 42575^2 + 2372^2 .

It is a cyclic number.

It is not a de Polignac number, because 1818257009 - 2¹² = 1818252913 is a prime.

Together with 1818257011, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1818257069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 909128504 + 909128505.

It is an arithmetic number, because the mean of its divisors is an integer number (909128505).

Almost surely, 2^1818257009 is an apocalyptic number.

It is an amenable number.

1818257009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1818257009 is an equidigital number, since it uses as much as digits as its factorization.

1818257009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 41.

The square root of 1818257009 is about 42641.0249525032. The cubic root of 1818257009 is about 1220.5392691199.

The spelling of 1818257009 in words is "one billion, eight hundred eighteen million, two hundred fifty-seven thousand, nine".