20725312709 has 2 divisors, whose sum is σ = 20725312710. Its totient is φ = 20725312708.

The previous prime is 20725312703. The next prime is 20725312757. The reversal of 20725312709 is 90721352702.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19349644609 + 1375668100 = 139103^2 + 37090^2 .

It is a cyclic number.

It is not a de Polignac number, because 20725312709 - 2¹⁶ = 20725247173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20725312703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10362656354 + 10362656355.

It is an arithmetic number, because the mean of its divisors is an integer number (10362656355).

Almost surely, 2^20725312709 is an apocalyptic number.

It is an amenable number.

20725312709 is a deficient number, since it is larger than the sum of its proper divisors (1).

20725312709 is an equidigital number, since it uses as much as digits as its factorization.

20725312709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52920, while the sum is 38.

The spelling of 20725312709 in words is "twenty billion, seven hundred twenty-five million, three hundred twelve thousand, seven hundred nine".