20503387 has 2 divisors, whose sum is σ = 20503388. Its totient is φ = 20503386.

The previous prime is 20503367. The next prime is 20503391. The reversal of 20503387 is 78330502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20503387 - 2¹¹ = 20501339 is a prime.

It is not a weakly prime, because it can be changed into another prime (20503367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10251693 + 10251694.

It is an arithmetic number, because the mean of its divisors is an integer number (10251694).

Almost surely, 2^20503387 is an apocalyptic number.

20503387 is a deficient number, since it is larger than the sum of its proper divisors (1).

20503387 is an equidigital number, since it uses as much as digits as its factorization.

20503387 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 20503387 is about 4528.0665851995. The cubic root of 20503387 is about 273.7002556207.

Adding to 20503387 its reverse (78330502), we get a palindrome (98833889).

It can be divided in two parts, 205033 and 87, that added together give a triangular number (205120 = T₆₄₀).

The spelling of 20503387 in words is "twenty million, five hundred three thousand, three hundred eighty-seven".