1840021 has 8 divisors (see below), whose sum is σ = 1933920. Its totient is φ = 1748208.

The previous prime is 1840019. The next prime is 1840031. The reversal of 1840021 is 1200481.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1840021 - 2¹ = 1840019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1839977 and 1840004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1840031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1470 + ... + 2416.

It is an arithmetic number, because the mean of its divisors is an integer number (241740).

2^1840021 is an apocalyptic number.

It is an amenable number.

1840021 is a deficient number, since it is larger than the sum of its proper divisors (93899).

1840021 is an equidigital number, since it uses as much as digits as its factorization.

1840021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 1840021 is about 1356.4737373057. The cubic root of 1840021 is about 122.5389796819.

The spelling of 1840021 in words is "one million, eight hundred forty thousand, twenty-one".