20006665537 has 2 divisors, whose sum is σ = 20006665538. Its totient is φ = 20006665536.

The previous prime is 20006665531. The next prime is 20006665589. The reversal of 20006665537 is 73556660002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19307380401 + 699285136 = 138951^2 + 26444^2 .

It is a cyclic number.

It is not a de Polignac number, because 20006665537 - 2¹¹ = 20006663489 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20006665537.

It is not a weakly prime, because it can be changed into another prime (20006665531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10003332768 + 10003332769.

It is an arithmetic number, because the mean of its divisors is an integer number (10003332769).

Almost surely, 2^20006665537 is an apocalyptic number.

It is an amenable number.

20006665537 is a deficient number, since it is larger than the sum of its proper divisors (1).

20006665537 is an equidigital number, since it uses as much as digits as its factorization.

20006665537 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 226800, while the sum is 40.

The spelling of 20006665537 in words is "twenty billion, six million, six hundred sixty-five thousand, five hundred thirty-seven".