20675420081 has 2 divisors, whose sum is σ = 20675420082. Its totient is φ = 20675420080.

The previous prime is 20675420063. The next prime is 20675420083. The reversal of 20675420081 is 18002457602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16497090481 + 4178329600 = 128441^2 + 64640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20675420081 is a prime.

It is a super-2 number, since 2×20675420081² (a number of 21 digits) contains 22 as substring.

Together with 20675420083, 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 (20675420083) 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, 10337710040 + 10337710041.

It is an arithmetic number, because the mean of its divisors is an integer number (10337710041).

Almost surely, 2^20675420081 is an apocalyptic number.

It is an amenable number.

20675420081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20675420081 is an equidigital number, since it uses as much as digits as its factorization.

20675420081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 35.

Adding to 20675420081 its reverse (18002457602), we get a palindrome (38677877683).

The spelling of 20675420081 in words is "twenty billion, six hundred seventy-five million, four hundred twenty thousand, eighty-one".