20814191 has 2 divisors, whose sum is σ = 20814192. Its totient is φ = 20814190.

The previous prime is 20814169. The next prime is 20814203. The reversal of 20814191 is 19141802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20814191 - 2⁶ = 20814127 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20814191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20814161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10407095 + 10407096.

It is an arithmetic number, because the mean of its divisors is an integer number (10407096).

Almost surely, 2^20814191 is an apocalyptic number.

20814191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20814191 is an equidigital number, since it uses as much as digits as its factorization.

20814191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 20814191 is about 4562.2572264176. The cubic root of 20814191 is about 275.0763027937.

Adding to 20814191 its reverse (19141802), we get a palindrome (39955993).

The spelling of 20814191 in words is "twenty million, eight hundred fourteen thousand, one hundred ninety-one".