3900324805781 has 2 divisors, whose sum is σ = 3900324805782. Its totient is φ = 3900324805780.

The previous prime is 3900324805739. The next prime is 3900324805813. The reversal of 3900324805781 is 1875084230093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3865808739556 + 34516066225 = 1966166^2 + 185785^2 .

It is a cyclic number.

It is not a de Polignac number, because 3900324805781 - 2¹⁰ = 3900324804757 is a prime.

It is a super-2 number, since 2×3900324805781² (a number of 26 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3900324825781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1950162402890 + 1950162402891.

It is an arithmetic number, because the mean of its divisors is an integer number (1950162402891).

Almost surely, 2^{3900324805781} is an apocalyptic number.

It is an amenable number.

3900324805781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3900324805781 is an equidigital number, since it uses as much as digits as its factorization.

3900324805781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1451520, while the sum is 50.

The spelling of 3900324805781 in words is "three trillion, nine hundred billion, three hundred twenty-four million, eight hundred five thousand, seven hundred eighty-one".