18305813 has 2 divisors, whose sum is σ = 18305814. Its totient is φ = 18305812.

The previous prime is 18305789. The next prime is 18305827. The reversal of 18305813 is 31850381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12439729 + 5866084 = 3527^2 + 2422^2 .

It is a cyclic number.

It is not a de Polignac number, because 18305813 - 2¹⁰ = 18304789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18304813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9152906 + 9152907.

It is an arithmetic number, because the mean of its divisors is an integer number (9152907).

Almost surely, 2^18305813 is an apocalyptic number.

It is an amenable number.

18305813 is a deficient number, since it is larger than the sum of its proper divisors (1).

18305813 is an equidigital number, since it uses as much as digits as its factorization.

18305813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 18305813 is about 4278.5293033939. The cubic root of 18305813 is about 263.5499918951.

The spelling of 18305813 in words is "eighteen million, three hundred five thousand, eight hundred thirteen".