1820849 has 4 divisors (see below), whose sum is σ = 1827840. Its totient is φ = 1813860.

The previous prime is 1820843. The next prime is 1820857. The reversal of 1820849 is 9480281.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1820849 - 2²⁰ = 772273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1820843) 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, 3089 + ... + 3630.

It is an arithmetic number, because the mean of its divisors is an integer number (456960).

2^1820849 is an apocalyptic number.

It is an amenable number.

1820849 is a deficient number, since it is larger than the sum of its proper divisors (6991).

1820849 is an equidigital number, since it uses as much as digits as its factorization.

1820849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6990.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 1820849 is about 1349.3883799707. The cubic root of 1820849 is about 122.1118968009. Note that the first 3 decimals are identical.

The spelling of 1820849 in words is "one million, eight hundred twenty thousand, eight hundred forty-nine".