1840813 has 4 divisors (see below), whose sum is σ = 1982428. Its totient is φ = 1699200.

The previous prime is 1840789. The next prime is 1840829. The reversal of 1840813 is 3180481.

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 1205604 + 635209 = 1098^2 + 797^2 .

It is a cyclic number.

It is not a de Polignac number, because 1840813 - 2⁵ = 1840781 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 (1840843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70788 + ... + 70813.

It is an arithmetic number, because the mean of its divisors is an integer number (495607).

2^1840813 is an apocalyptic number.

1840813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1840813 is a deficient number, since it is larger than the sum of its proper divisors (141615).

1840813 is a wasteful number, since it uses less digits than its factorization.

1840813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141614.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 1840813 is about 1356.7656393055. The cubic root of 1840813 is about 122.5565586390.

The spelling of 1840813 in words is "one million, eight hundred forty thousand, eight hundred thirteen".