2128891 has 2 divisors, whose sum is σ = 2128892. Its totient is φ = 2128890.

The previous prime is 2128873. The next prime is 2128933. The reversal of 2128891 is 1988212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2128891 - 2¹⁵ = 2096123 is a prime.

It is not a weakly prime, because it can be changed into another prime (2128831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1064445 + 1064446.

It is an arithmetic number, because the mean of its divisors is an integer number (1064446).

2^2128891 is an apocalyptic number.

2128891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2128891 is an equidigital number, since it uses as much as digits as its factorization.

2128891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304, while the sum is 31.

The square root of 2128891 is about 1459.0719653259. The cubic root of 2128891 is about 128.6425011516.

The spelling of 2128891 in words is "two million, one hundred twenty-eight thousand, eight hundred ninety-one".