20800081 has 2 divisors, whose sum is σ = 20800082. Its totient is φ = 20800080.

The previous prime is 20800033. The next prime is 20800093. The reversal of 20800081 is 18000802.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17505856 + 3294225 = 4184^2 + 1815^2 .

It is a cyclic number.

It is not a de Polignac number, because 20800081 - 2¹⁷ = 20669009 is a prime.

It is a super-2 number, since 2×20800081² = 865286739213122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20800181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10400040 + 10400041.

It is an arithmetic number, because the mean of its divisors is an integer number (10400041).

Almost surely, 2^20800081 is an apocalyptic number.

It is an amenable number.

20800081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20800081 is an equidigital number, since it uses as much as digits as its factorization.

20800081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 20800081 is about 4560.7105806004. The cubic root of 20800081 is about 275.0141304034.

Adding to 20800081 its reverse (18000802), we get a palindrome (38800883).

The spelling of 20800081 in words is "twenty million, eight hundred thousand, eighty-one".