4004081 has 2 divisors, whose sum is σ = 4004082. Its totient is φ = 4004080.

The previous prime is 4004069. The next prime is 4004087. The reversal of 4004081 is 1804004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3964081 + 40000 = 1991^2 + 200^2 .

It is a cyclic number.

It is not a de Polignac number, because 4004081 - 2¹⁰ = 4003057 is a prime.

It is a super-2 number, since 2×4004081² = 32065329309122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (4004087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2002040 + 2002041.

It is an arithmetic number, because the mean of its divisors is an integer number (2002041).

Almost surely, 2^4004081 is an apocalyptic number.

It is an amenable number.

4004081 is a deficient number, since it is larger than the sum of its proper divisors (1).

4004081 is an equidigital number, since it uses as much as digits as its factorization.

4004081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 4004081 is about 2001.0199899051. The cubic root of 4004081 is about 158.7940717120.

Adding to 4004081 its reverse (1804004), we get a palindrome (5808085).

The spelling of 4004081 in words is "four million, four thousand, eighty-one".