2189941891 has 2 divisors, whose sum is σ = 2189941892. Its totient is φ = 2189941890.

The previous prime is 2189941877. The next prime is 2189941913. The reversal of 2189941891 is 1981499812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2189941891 - 2⁹ = 2189941379 is a prime.

It is not a weakly prime, because it can be changed into another prime (2189941811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1094970945 + 1094970946.

It is an arithmetic number, because the mean of its divisors is an integer number (1094970946).

Almost surely, 2^2189941891 is an apocalyptic number.

2189941891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2189941891 is an equidigital number, since it uses as much as digits as its factorization.

2189941891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 373248, while the sum is 52.

The square root of 2189941891 is about 46796.8149664056. The cubic root of 2189941891 is about 1298.6063745875.

The spelling of 2189941891 in words is "two billion, one hundred eighty-nine million, nine hundred forty-one thousand, eight hundred ninety-one".