4002031021 has 2 divisors, whose sum is σ = 4002031022. Its totient is φ = 4002031020.

The previous prime is 4002030997. The next prime is 4002031043. The reversal of 4002031021 is 1201302004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3625244100 + 376786921 = 60210^2 + 19411^2 .

It is a cyclic number.

It is not a de Polignac number, because 4002031021 - 2⁹ = 4002030509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 4002030992 and 4002031010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4002031051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2001015510 + 2001015511.

It is an arithmetic number, because the mean of its divisors is an integer number (2001015511).

Almost surely, 2^4002031021 is an apocalyptic number.

It is an amenable number.

4002031021 is a deficient number, since it is larger than the sum of its proper divisors (1).

4002031021 is an equidigital number, since it uses as much as digits as its factorization.

4002031021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 4002031021 is about 63261.6077965143. The cubic root of 4002031021 is about 1587.6696769141.

Adding to 4002031021 its reverse (1201302004), we get a palindrome (5203333025).

The spelling of 4002031021 in words is "four billion, two million, thirty-one thousand, twenty-one".