20936258197 has 2 divisors, whose sum is σ = 20936258198. Its totient is φ = 20936258196.

The previous prime is 20936258179. The next prime is 20936258201. The reversal of 20936258197 is 79185263902.

Together with previous prime (20936258179) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20848760881 + 87497316 = 144391^2 + 9354^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20936258197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20936250197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10468129098 + 10468129099.

It is an arithmetic number, because the mean of its divisors is an integer number (10468129099).

Almost surely, 2^20936258197 is an apocalyptic number.

It is an amenable number.

20936258197 is a deficient number, since it is larger than the sum of its proper divisors (1).

20936258197 is an equidigital number, since it uses as much as digits as its factorization.

20936258197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 20936258197 in words is "twenty billion, nine hundred thirty-six million, two hundred fifty-eight thousand, one hundred ninety-seven".