1990841 has 4 divisors (see below), whose sum is σ = 2013300. Its totient is φ = 1968384.

The previous prime is 1990831. The next prime is 1990867. The reversal of 1990841 is 1480991.

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 633616 + 1357225 = 796^2 + 1165^2 .

It is a cyclic number.

It is not a de Polignac number, because 1990841 - 2¹⁴ = 1974457 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1990798 and 1990807.

It is not an unprimeable number, because it can be changed into a prime (1990831) 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, 11096 + ... + 11273.

It is an arithmetic number, because the mean of its divisors is an integer number (503325).

2^1990841 is an apocalyptic number.

It is an amenable number.

1990841 is a deficient number, since it is larger than the sum of its proper divisors (22459).

1990841 is an equidigital number, since it uses as much as digits as its factorization.

1990841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22458.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 1990841 is about 1410.9716510263. The cubic root of 1990841 is about 125.7994837049.

The spelling of 1990841 in words is "one million, nine hundred ninety thousand, eight hundred forty-one".