4005124221 has 16 divisors (see below), whose sum is σ = 6227600000. Its totient is φ = 2288641824.

The previous prime is 4005124217. The next prime is 4005124229. The reversal of 4005124221 is 1224215004.

It is not a de Polignac number, because 4005124221 - 2² = 4005124217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

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 (4005124229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1945096 + ... + 1947153.

It is an arithmetic number, because the mean of its divisors is an integer number (389225000).

Almost surely, 2^4005124221 is an apocalyptic number.

It is an amenable number.

4005124221 is a deficient number, since it is larger than the sum of its proper divisors (2222475779).

4005124221 is an equidigital number, since it uses as much as digits as its factorization.

4005124221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3892273 (or 3892259 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 4005124221 is about 63286.0507616015. The cubic root of 4005124221 is about 1588.0786122036.

Adding to 4005124221 its reverse (1224215004), we get a palindrome (5229339225).

The spelling of 4005124221 in words is "four billion, five million, one hundred twenty-four thousand, two hundred twenty-one".