1821738 has 32 divisors (see below), whose sum is σ = 3902976. Its totient is φ = 565488.

The previous prime is 1821733. The next prime is 1821749. The reversal of 1821738 is 8371281.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1821731) 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 15 ways as a sum of consecutive naturals, for example, 5781 + ... + 6087.

It is an arithmetic number, because the mean of its divisors is an integer number (121968).

2^1821738 is an apocalyptic number.

1821738 is an abundant number, since it is smaller than the sum of its proper divisors (2081238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1821738 is a wasteful number, since it uses less digits than its factorization.

1821738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378.

The product of its digits is 2688, while the sum is 30.

The square root of 1821738 is about 1349.7177482718. The cubic root of 1821738 is about 122.1317666187.

The spelling of 1821738 in words is "one million, eight hundred twenty-one thousand, seven hundred thirty-eight".