20311801918193 has 2 divisors, whose sum is σ = 20311801918194. Its totient is φ = 20311801918192.

The previous prime is 20311801918181. The next prime is 20311801918249. The reversal of 20311801918193 is 39181910811302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18666400534369 + 1645401383824 = 4320463^2 + 1282732^2 .

It is a cyclic number.

It is not a de Polignac number, because 20311801918193 - 2³² = 20307506950897 is a prime.

It is not a weakly prime, because it can be changed into another prime (20311801914193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10155900959096 + 10155900959097.

It is an arithmetic number, because the mean of its divisors is an integer number (10155900959097).

Almost surely, 2^{20311801918193} is an apocalyptic number.

It is an amenable number.

20311801918193 is a deficient number, since it is larger than the sum of its proper divisors (1).

20311801918193 is an equidigital number, since it uses as much as digits as its factorization.

20311801918193 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 47.

The spelling of 20311801918193 in words is "twenty trillion, three hundred eleven billion, eight hundred one million, nine hundred eighteen thousand, one hundred ninety-three".