20191043 has 2 divisors, whose sum is σ = 20191044. Its totient is φ = 20191042.

The previous prime is 20191027. The next prime is 20191049. The reversal of 20191043 is 34019102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20191043 - 2⁴ = 20191027 is a prime.

It is not a weakly prime, because it can be changed into another prime (20191049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10095521 + 10095522.

It is an arithmetic number, because the mean of its divisors is an integer number (10095522).

Almost surely, 2^20191043 is an apocalyptic number.

20191043 is a deficient number, since it is larger than the sum of its proper divisors (1).

20191043 is an equidigital number, since it uses as much as digits as its factorization.

20191043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 20191043 is about 4493.4444471919. Note that the first 5 decimals coincide. The cubic root of 20191043 is about 272.3033083882.

The spelling of 20191043 in words is "twenty million, one hundred ninety-one thousand, forty-three".