4021805 has 8 divisors (see below), whose sum is σ = 4849152. Its totient is φ = 3202128.

The previous prime is 4021777. The next prime is 4021867. The reversal of 4021805 is 5081204.

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 4021805 - 2¹⁰ = 4020781 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 689 + ... + 2918.

It is an arithmetic number, because the mean of its divisors is an integer number (606144).

Almost surely, 2^4021805 is an apocalyptic number.

It is an amenable number.

4021805 is a deficient number, since it is larger than the sum of its proper divisors (827347).

4021805 is a wasteful number, since it uses less digits than its factorization.

4021805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3835.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 4021805 is about 2005.4438411484. The cubic root of 4021805 is about 159.0280266511.

The spelling of 4021805 in words is "four million, twenty-one thousand, eight hundred five".