20507558317 has 2 divisors, whose sum is σ = 20507558318. Its totient is φ = 20507558316.

The previous prime is 20507558311. The next prime is 20507558369. The reversal of 20507558317 is 71385570502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16946572041 + 3560986276 = 130179^2 + 59674^2 .

It is a cyclic number.

It is not a de Polignac number, because 20507558317 - 2¹⁹ = 20507034029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20507558311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10253779158 + 10253779159.

It is an arithmetic number, because the mean of its divisors is an integer number (10253779159).

Almost surely, 2^20507558317 is an apocalyptic number.

It is an amenable number.

20507558317 is a deficient number, since it is larger than the sum of its proper divisors (1).

20507558317 is an equidigital number, since it uses as much as digits as its factorization.

20507558317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 294000, while the sum is 43.

The spelling of 20507558317 in words is "twenty billion, five hundred seven million, five hundred fifty-eight thousand, three hundred seventeen".