4001043521 has 2 divisors, whose sum is σ = 4001043522. Its totient is φ = 4001043520.

The previous prime is 4001043481. The next prime is 4001043533. The reversal of 4001043521 is 1253401004.

4001043521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2323240000 + 1677803521 = 48200^2 + 40961^2 .

It is a cyclic number.

It is not a de Polignac number, because 4001043521 - 2⁶ = 4001043457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 4001043493 and 4001043502.

It is not a weakly prime, because it can be changed into another prime (4001043121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2000521760 + 2000521761.

It is an arithmetic number, because the mean of its divisors is an integer number (2000521761).

Almost surely, 2^4001043521 is an apocalyptic number.

It is an amenable number.

4001043521 is a deficient number, since it is larger than the sum of its proper divisors (1).

4001043521 is an equidigital number, since it uses as much as digits as its factorization.

4001043521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 4001043521 is about 63253.8024232536. The cubic root of 4001043521 is about 1587.5390804937.

Adding to 4001043521 its reverse (1253401004), we get a palindrome (5254444525).

The spelling of 4001043521 in words is "four billion, one million, forty-three thousand, five hundred twenty-one".