4080821 has 4 divisors (see below), whose sum is σ = 4258272. Its totient is φ = 3903372.

The previous prime is 4080803. The next prime is 4080827. The reversal of 4080821 is 1280804.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4080821 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 177427 = 4080821 / (4 + 0 + 8 + 0 + 8 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4080827) 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, 88691 + ... + 88736.

It is an arithmetic number, because the mean of its divisors is an integer number (1064568).

Almost surely, 2^4080821 is an apocalyptic number.

It is an amenable number.

4080821 is a deficient number, since it is larger than the sum of its proper divisors (177451).

4080821 is a wasteful number, since it uses less digits than its factorization.

4080821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177450.

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

The square root of 4080821 is about 2020.1042052330. The cubic root of 4080821 is about 159.8021121242.

The spelling of 4080821 in words is "four million, eighty thousand, eight hundred twenty-one".