20681467693 has 2 divisors, whose sum is σ = 20681467694. Its totient is φ = 20681467692.

The previous prime is 20681467661. The next prime is 20681467771. The reversal of 20681467693 is 39676418602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10581619689 + 10099848004 = 102867^2 + 100498^2 .

It is a cyclic number.

It is not a de Polignac number, because 20681467693 - 2⁵ = 20681467661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20681467693.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20681467613) 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, 10340733846 + 10340733847.

It is an arithmetic number, because the mean of its divisors is an integer number (10340733847).

Almost surely, 2^20681467693 is an apocalyptic number.

It is an amenable number.

20681467693 is a deficient number, since it is larger than the sum of its proper divisors (1).

20681467693 is an equidigital number, since it uses as much as digits as its factorization.

20681467693 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2612736, while the sum is 52.

The spelling of 20681467693 in words is "twenty billion, six hundred eighty-one million, four hundred sixty-seven thousand, six hundred ninety-three".