20665567001 has 2 divisors, whose sum is σ = 20665567002. Its totient is φ = 20665567000.

The previous prime is 20665566997. The next prime is 20665567009. The reversal of 20665567001 is 10076556602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20413551376 + 252015625 = 142876^2 + 15875^2 .

It is a cyclic number.

It is not a de Polignac number, because 20665567001 - 2² = 20665566997 is a prime.

It is not a weakly prime, because it can be changed into another prime (20665567009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10332783500 + 10332783501.

It is an arithmetic number, because the mean of its divisors is an integer number (10332783501).

Almost surely, 2^20665567001 is an apocalyptic number.

It is an amenable number.

20665567001 is a deficient number, since it is larger than the sum of its proper divisors (1).

20665567001 is an equidigital number, since it uses as much as digits as its factorization.

20665567001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 20665567001 in words is "twenty billion, six hundred sixty-five million, five hundred sixty-seven thousand, one".