3971681291 has 2 divisors, whose sum is σ = 3971681292. Its totient is φ = 3971681290.

The previous prime is 3971681267. The next prime is 3971681303. The reversal of 3971681291 is 1921861793.

3971681291 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 is an emirp because it is prime and its reverse (1921861793) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3971681291 - 2⁶ = 3971681227 is a prime.

It is not a weakly prime, because it can be changed into another prime (3971681221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1985840645 + 1985840646.

It is an arithmetic number, because the mean of its divisors is an integer number (1985840646).

Almost surely, 2^3971681291 is an apocalyptic number.

3971681291 is a deficient number, since it is larger than the sum of its proper divisors (1).

3971681291 is an equidigital number, since it uses as much as digits as its factorization.

3971681291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 163296, while the sum is 47.

The square root of 3971681291 is about 63021.2764945300. The cubic root of 3971681291 is about 1583.6460809451.

The spelling of 3971681291 in words is "three billion, nine hundred seventy-one million, six hundred eighty-one thousand, two hundred ninety-one".