3938470721 has 2 divisors, whose sum is σ = 3938470722. Its totient is φ = 3938470720.

The previous prime is 3938470717. The next prime is 3938470759. The reversal of 3938470721 is 1270748393.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3661581121 + 276889600 = 60511^2 + 16640^2 .

It is a cyclic number.

It is not a de Polignac number, because 3938470721 - 2² = 3938470717 is a prime.

It is not a weakly prime, because it can be changed into another prime (3938470321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1969235360 + 1969235361.

It is an arithmetic number, because the mean of its divisors is an integer number (1969235361).

Almost surely, 2^3938470721 is an apocalyptic number.

It is an amenable number.

3938470721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3938470721 is an equidigital number, since it uses as much as digits as its factorization.

3938470721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 254016, while the sum is 44.

The square root of 3938470721 is about 62757.2364034619. The cubic root of 3938470721 is about 1579.2196543159.

The spelling of 3938470721 in words is "three billion, nine hundred thirty-eight million, four hundred seventy thousand, seven hundred twenty-one".