1820365 has 4 divisors (see below), whose sum is σ = 2184444. Its totient is φ = 1456288.

The previous prime is 1820353. The next prime is 1820387. The reversal of 1820365 is 5630281.

It is a happy number.

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 777924 + 1042441 = 882^2 + 1021^2 .

It is a cyclic number.

It is not a de Polignac number, because 1820365 - 2⁷ = 1820237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 182032 + ... + 182041.

It is an arithmetic number, because the mean of its divisors is an integer number (546111).

2^1820365 is an apocalyptic number.

It is an amenable number.

1820365 is a deficient number, since it is larger than the sum of its proper divisors (364079).

1820365 is an equidigital number, since it uses as much as digits as its factorization.

1820365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364078.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 1820365 is about 1349.2090275417. The cubic root of 1820365 is about 122.1010763181.

The spelling of 1820365 in words is "one million, eight hundred twenty thousand, three hundred sixty-five".