20861806073 has 2 divisors, whose sum is σ = 20861806074. Its totient is φ = 20861806072.

The previous prime is 20861806039. The next prime is 20861806093. The reversal of 20861806073 is 37060816802.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11466768889 + 9395037184 = 107083^2 + 96928^2 .

It is a cyclic number.

It is not a de Polignac number, because 20861806073 - 2⁸ = 20861805817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20861806073.

It is not a weakly prime, because it can be changed into another prime (20861806033) 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, 10430903036 + 10430903037.

It is an arithmetic number, because the mean of its divisors is an integer number (10430903037).

Almost surely, 2^20861806073 is an apocalyptic number.

It is an amenable number.

20861806073 is a deficient number, since it is larger than the sum of its proper divisors (1).

20861806073 is an equidigital number, since it uses as much as digits as its factorization.

20861806073 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 41.

The spelling of 20861806073 in words is "twenty billion, eight hundred sixty-one million, eight hundred six thousand, seventy-three".