1681158191 has 2 divisors, whose sum is σ = 1681158192. Its totient is φ = 1681158190.

The previous prime is 1681158139. The next prime is 1681158253. The reversal of 1681158191 is 1918511861.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1681158191 - 2¹⁴ = 1681141807 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681152191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840579095 + 840579096.

It is an arithmetic number, because the mean of its divisors is an integer number (840579096).

Almost surely, 2^1681158191 is an apocalyptic number.

1681158191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681158191 is an equidigital number, since it uses as much as digits as its factorization.

1681158191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 41.

The square root of 1681158191 is about 41001.9291131527. The cubic root of 1681158191 is about 1189.0575102165.

The spelling of 1681158191 in words is "one billion, six hundred eighty-one million, one hundred fifty-eight thousand, one hundred ninety-one".