18235813 has 2 divisors, whose sum is σ = 18235814. Its totient is φ = 18235812.

The previous prime is 18235799. The next prime is 18235829. The reversal of 18235813 is 31853281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14303524 + 3932289 = 3782^2 + 1983^2 .

It is a cyclic number.

It is not a de Polignac number, because 18235813 - 2¹⁷ = 18104741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18230813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9117906 + 9117907.

It is an arithmetic number, because the mean of its divisors is an integer number (9117907).

Almost surely, 2^18235813 is an apocalyptic number.

It is an amenable number.

18235813 is a deficient number, since it is larger than the sum of its proper divisors (1).

18235813 is an equidigital number, since it uses as much as digits as its factorization.

18235813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 31.

The square root of 18235813 is about 4270.3410870796. The cubic root of 18235813 is about 263.2136312588.

The spelling of 18235813 in words is "eighteen million, two hundred thirty-five thousand, eight hundred thirteen".