208403680081 has 2 divisors, whose sum is σ = 208403680082. Its totient is φ = 208403680080.

The previous prime is 208403680061. The next prime is 208403680099. The reversal of 208403680081 is 180086304802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196086009856 + 12317670225 = 442816^2 + 110985^2 .

It is a cyclic number.

It is not a de Polignac number, because 208403680081 - 2⁵ = 208403680049 is a prime.

It is a super-2 number, since 2×208403680081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (208403680021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104201840040 + 104201840041.

It is an arithmetic number, because the mean of its divisors is an integer number (104201840041).

Almost surely, 2^208403680081 is an apocalyptic number.

It is an amenable number.

208403680081 is a deficient number, since it is larger than the sum of its proper divisors (1).

208403680081 is an equidigital number, since it uses as much as digits as its factorization.

208403680081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 73728, while the sum is 40.

Adding to 208403680081 its reverse (180086304802), we get a palindrome (388489984883).

The spelling of 208403680081 in words is "two hundred eight billion, four hundred three million, six hundred eighty thousand, eighty-one".