2021798 has 4 divisors (see below), whose sum is σ = 3032700. Its totient is φ = 1010898.

The previous prime is 2021783. The next prime is 2021801. The reversal of 2021798 is 8971202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8971202 = 2 ⋅4485601.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2021798.

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 as a sum of consecutive naturals, namely, 505448 + ... + 505451.

It is an arithmetic number, because the mean of its divisors is an integer number (758175).

2^2021798 is an apocalyptic number.

2021798 is a deficient number, since it is larger than the sum of its proper divisors (1010902).

2021798 is a wasteful number, since it uses less digits than its factorization.

2021798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1010901.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 2021798 is about 1421.8994338560. The cubic root of 2021798 is about 126.4481813728.

The spelling of 2021798 in words is "two million, twenty-one thousand, seven hundred ninety-eight".