4021813 has 8 divisors (see below), whose sum is σ = 4147416. Its totient is φ = 3897600.

The previous prime is 4021777. The next prime is 4021867. The reversal of 4021813 is 3181204.

It can be written as a sum of positive squares in 4 ways, for example, as 628849 + 3392964 = 793^2 + 1842^2 .

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 4021813 - 2⁹ = 4021301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4021873) 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, 9343 + ... + 9763.

It is an arithmetic number, because the mean of its divisors is an integer number (518427).

Almost surely, 2^4021813 is an apocalyptic number.

It is an amenable number.

4021813 is a deficient number, since it is larger than the sum of its proper divisors (125603).

4021813 is a wasteful number, since it uses less digits than its factorization.

4021813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 4021813 is about 2005.4458357183. The cubic root of 4021813 is about 159.0281320949.

The spelling of 4021813 in words is "four million, twenty-one thousand, eight hundred thirteen".