20388192217 has 2 divisors, whose sum is σ = 20388192218. Its totient is φ = 20388192216.

The previous prime is 20388192113. The next prime is 20388192239. The reversal of 20388192217 is 71229188302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17231550361 + 3156641856 = 131269^2 + 56184^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20388192217 is a prime.

It is not a weakly prime, because it can be changed into another prime (20388192247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10194096108 + 10194096109.

It is an arithmetic number, because the mean of its divisors is an integer number (10194096109).

Almost surely, 2^20388192217 is an apocalyptic number.

It is an amenable number.

20388192217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20388192217 is an equidigital number, since it uses as much as digits as its factorization.

20388192217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 43.

The spelling of 20388192217 in words is "twenty billion, three hundred eighty-eight million, one hundred ninety-two thousand, two hundred seventeen".