20713125217 has 2 divisors, whose sum is σ = 20713125218. Its totient is φ = 20713125216.

The previous prime is 20713125179. The next prime is 20713125229. The reversal of 20713125217 is 71252131702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20668087696 + 45037521 = 143764^2 + 6711^2 .

It is a cyclic number.

It is not a de Polignac number, because 20713125217 - 2²³ = 20704736609 is a prime.

It is not a weakly prime, because it can be changed into another prime (20713825217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10356562608 + 10356562609.

It is an arithmetic number, because the mean of its divisors is an integer number (10356562609).

Almost surely, 2^20713125217 is an apocalyptic number.

It is an amenable number.

20713125217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20713125217 is an equidigital number, since it uses as much as digits as its factorization.

20713125217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5880, while the sum is 31.

Adding to 20713125217 its reverse (71252131702), we get a palindrome (91965256919).

The spelling of 20713125217 in words is "twenty billion, seven hundred thirteen million, one hundred twenty-five thousand, two hundred seventeen".