20503481 has 2 divisors, whose sum is σ = 20503482. Its totient is φ = 20503480.

The previous prime is 20503463. The next prime is 20503501. The reversal of 20503481 is 18430502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17472400 + 3031081 = 4180^2 + 1741^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20503481 is a prime.

It is a super-2 number, since 2×20503481² = 840785466234722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20503981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10251740 + 10251741.

It is an arithmetic number, because the mean of its divisors is an integer number (10251741).

Almost surely, 2^20503481 is an apocalyptic number.

It is an amenable number.

20503481 is a deficient number, since it is larger than the sum of its proper divisors (1).

20503481 is an equidigital number, since it uses as much as digits as its factorization.

20503481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 20503481 is about 4528.0769648936. The cubic root of 20503481 is about 273.7006738896.

Adding to 20503481 its reverse (18430502), we get a palindrome (38933983).

The spelling of 20503481 in words is "twenty million, five hundred three thousand, four hundred eighty-one".