20420503 has 2 divisors, whose sum is σ = 20420504. Its totient is φ = 20420502.

The previous prime is 20420479. The next prime is 20420531. The reversal of 20420503 is 30502402.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20420503 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20420563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10210251 + 10210252.

It is an arithmetic number, because the mean of its divisors is an integer number (10210252).

Almost surely, 2^20420503 is an apocalyptic number.

20420503 is a deficient number, since it is larger than the sum of its proper divisors (1).

20420503 is an equidigital number, since it uses as much as digits as its factorization.

20420503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 20420503 is about 4518.9050664956. The cubic root of 20420503 is about 273.3309506369.

Adding to 20420503 its reverse (30502402), we get a palindrome (50922905).

The spelling of 20420503 in words is "twenty million, four hundred twenty thousand, five hundred three".