3956985121 has 2 divisors, whose sum is σ = 3956985122. Its totient is φ = 3956985120.

The previous prime is 3956985089. The next prime is 3956985133. The reversal of 3956985121 is 1215896593.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3403088896 + 553896225 = 58336^2 + 23535^2 .

It is a cyclic number.

It is not a de Polignac number, because 3956985121 - 2⁵ = 3956985089 is a prime.

It is not a weakly prime, because it can be changed into another prime (3956985181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1978492560 + 1978492561.

It is an arithmetic number, because the mean of its divisors is an integer number (1978492561).

Almost surely, 2^3956985121 is an apocalyptic number.

It is an amenable number.

3956985121 is a deficient number, since it is larger than the sum of its proper divisors (1).

3956985121 is an equidigital number, since it uses as much as digits as its factorization.

3956985121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 583200, while the sum is 49.

The square root of 3956985121 is about 62904.5715429332. The cubic root of 3956985121 is about 1581.6903771048.

The spelling of 3956985121 in words is "three billion, nine hundred fifty-six million, nine hundred eighty-five thousand, one hundred twenty-one".