20808570481 has 2 divisors, whose sum is σ = 20808570482. Its totient is φ = 20808570480.

The previous prime is 20808570473. The next prime is 20808570539. The reversal of 20808570481 is 18407580802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17693256256 + 3115314225 = 133016^2 + 55815^2 .

It is a cyclic number.

It is not a de Polignac number, because 20808570481 - 2³ = 20808570473 is a prime.

It is a super-2 number, since 2×20808570481² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20808570451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10404285240 + 10404285241.

It is an arithmetic number, because the mean of its divisors is an integer number (10404285241).

Almost surely, 2^20808570481 is an apocalyptic number.

It is an amenable number.

20808570481 is a deficient number, since it is larger than the sum of its proper divisors (1).

20808570481 is an equidigital number, since it uses as much as digits as its factorization.

20808570481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 143360, while the sum is 43.

The spelling of 20808570481 in words is "twenty billion, eight hundred eight million, five hundred seventy thousand, four hundred eighty-one".