1813813 has 2 divisors, whose sum is σ = 1813814. Its totient is φ = 1813812.

The previous prime is 1813793. The next prime is 1813817. The reversal of 1813813 is 3183181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1787569 + 26244 = 1337^2 + 162^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1813813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1813817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 906906 + 906907.

It is an arithmetic number, because the mean of its divisors is an integer number (906907).

2^1813813 is an apocalyptic number.

It is an amenable number.

1813813 is a deficient number, since it is larger than the sum of its proper divisors (1).

1813813 is an equidigital number, since it uses as much as digits as its factorization.

1813813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 25.

The square root of 1813813 is about 1346.7787494611. The cubic root of 1813813 is about 121.9544082981.

Adding to 1813813 its reverse (3183181), we get a palindrome (4996994).

It can be divided in two parts, 18 and 13813, that added together give a palindrome (13831).

The spelling of 1813813 in words is "one million, eight hundred thirteen thousand, eight hundred thirteen".