20207281 has 2 divisors, whose sum is σ = 20207282. Its totient is φ = 20207280.

The previous prime is 20207269. The next prime is 20207303. The reversal of 20207281 is 18270202.

It is an a-pointer prime, because the next prime (20207303) can be obtained adding 20207281 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13024881 + 7182400 = 3609^2 + 2680^2 .

It is a cyclic number.

It is not a de Polignac number, because 20207281 - 2⁷ = 20207153 is a prime.

It is a super-2 number, since 2×20207281² = 816668410825922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20207221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10103640 + 10103641.

It is an arithmetic number, because the mean of its divisors is an integer number (10103641).

Almost surely, 2^20207281 is an apocalyptic number.

It is an amenable number.

20207281 is a deficient number, since it is larger than the sum of its proper divisors (1).

20207281 is an equidigital number, since it uses as much as digits as its factorization.

20207281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 20207281 is about 4495.2509384905. The cubic root of 20207281 is about 272.3762859015.

Adding to 20207281 its reverse (18270202), we get a palindrome (38477483).

The spelling of 20207281 in words is "twenty million, two hundred seven thousand, two hundred eighty-one".