20662606961 has 2 divisors, whose sum is σ = 20662606962. Its totient is φ = 20662606960.

The previous prime is 20662606931. The next prime is 20662606963. The reversal of 20662606961 is 16960626602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10766137600 + 9896469361 = 103760^2 + 99481^2 .

It is a cyclic number.

It is not a de Polignac number, because 20662606961 - 2⁶ = 20662606897 is a prime.

Together with 20662606963, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20662606963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10331303480 + 10331303481.

It is an arithmetic number, because the mean of its divisors is an integer number (10331303481).

Almost surely, 2^20662606961 is an apocalyptic number.

It is an amenable number.

20662606961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20662606961 is an equidigital number, since it uses as much as digits as its factorization.

20662606961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 44.

The spelling of 20662606961 in words is "twenty billion, six hundred sixty-two million, six hundred six thousand, nine hundred sixty-one".