2109143891 has 2 divisors, whose sum is σ = 2109143892. Its totient is φ = 2109143890.

The previous prime is 2109143867. The next prime is 2109143909. The reversal of 2109143891 is 1983419012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2109143891 - 2²⁶ = 2042035027 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (2109143801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1054571945 + 1054571946.

It is an arithmetic number, because the mean of its divisors is an integer number (1054571946).

Almost surely, 2^2109143891 is an apocalyptic number.

2109143891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2109143891 is an equidigital number, since it uses as much as digits as its factorization.

2109143891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 2109143891 is about 45925.4166121550. The cubic root of 2109143891 is about 1282.4351208650.

The spelling of 2109143891 in words is "two billion, one hundred nine million, one hundred forty-three thousand, eight hundred ninety-one".