1813397 has 4 divisors (see below), whose sum is σ = 1819116. Its totient is φ = 1807680.

The previous prime is 1813391. The next prime is 1813421. The reversal of 1813397 is 7933181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 538756 + 1274641 = 734^2 + 1129^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1813397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1813391) 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 in 3 ways as a sum of consecutive naturals, for example, 2354 + ... + 3027.

It is an arithmetic number, because the mean of its divisors is an integer number (454779).

2^1813397 is an apocalyptic number.

It is an amenable number.

1813397 is a deficient number, since it is larger than the sum of its proper divisors (5719).

1813397 is an equidigital number, since it uses as much as digits as its factorization.

1813397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5718.

The product of its digits is 4536, while the sum is 32.

The square root of 1813397 is about 1346.6242980134. The cubic root of 1813397 is about 121.9450841261.

The spelling of 1813397 in words is "one million, eight hundred thirteen thousand, three hundred ninety-seven".