20420133191 has 2 divisors, whose sum is σ = 20420133192. Its totient is φ = 20420133190.

The previous prime is 20420133133. The next prime is 20420133311. The reversal of 20420133191 is 19133102402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20420133191 - 2¹⁸ = 20419871047 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20420133191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20420133121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10210066595 + 10210066596.

It is an arithmetic number, because the mean of its divisors is an integer number (10210066596).

Almost surely, 2^20420133191 is an apocalyptic number.

20420133191 is a deficient number, since it is larger than the sum of its proper divisors (1).

20420133191 is an equidigital number, since it uses as much as digits as its factorization.

20420133191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 26.

Adding to 20420133191 its reverse (19133102402), we get a palindrome (39553235593).

The spelling of 20420133191 in words is "twenty billion, four hundred twenty million, one hundred thirty-three thousand, one hundred ninety-one".