20303681 has 2 divisors, whose sum is σ = 20303682. Its totient is φ = 20303680.

The previous prime is 20303663. The next prime is 20303707. The reversal of 20303681 is 18630302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18318400 + 1985281 = 4280^2 + 1409^2 .

It is a cyclic number.

It is not a de Polignac number, because 20303681 - 2¹⁴ = 20287297 is a prime.

It is a super-2 number, since 2×20303681² = 824478924299522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20303281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10151840 + 10151841.

It is an arithmetic number, because the mean of its divisors is an integer number (10151841).

Almost surely, 2^20303681 is an apocalyptic number.

It is an amenable number.

20303681 is a deficient number, since it is larger than the sum of its proper divisors (1).

20303681 is an equidigital number, since it uses as much as digits as its factorization.

20303681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 20303681 is about 4505.9606079059. The cubic root of 20303681 is about 272.8087278950.

Adding to 20303681 its reverse (18630302), we get a palindrome (38933983).

The spelling of 20303681 in words is "twenty million, three hundred three thousand, six hundred eighty-one".