4008821 has 4 divisors (see below), whose sum is σ = 4244652. Its totient is φ = 3772992.

The previous prime is 4008799. The next prime is 4008841. The reversal of 4008821 is 1288004.

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 1322500 + 2686321 = 1150^2 + 1639^2 .

It is a cyclic number.

It is not a de Polignac number, because 4008821 - 2¹⁰ = 4007797 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4008841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117890 + ... + 117923.

It is an arithmetic number, because the mean of its divisors is an integer number (1061163).

Almost surely, 2^4008821 is an apocalyptic number.

It is an amenable number.

4008821 is a deficient number, since it is larger than the sum of its proper divisors (235831).

4008821 is a wasteful number, since it uses less digits than its factorization.

4008821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235830.

The product of its (nonzero) digits is 512, while the sum is 23.

The square root of 4008821 is about 2002.2040355568. The cubic root of 4008821 is about 158.8567067326.

The spelling of 4008821 in words is "four million, eight thousand, eight hundred twenty-one".