20420403 has 4 divisors (see below), whose sum is σ = 27227208. Its totient is φ = 13613600.

The previous prime is 20420377. The next prime is 20420443. The reversal of 20420403 is 30402402.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20420403 - 2⁵ = 20420371 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20420443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3403398 + ... + 3403403.

It is an arithmetic number, because the mean of its divisors is an integer number (6806802).

Almost surely, 2^20420403 is an apocalyptic number.

20420403 is a deficient number, since it is larger than the sum of its proper divisors (6806805).

20420403 is an equidigital number, since it uses as much as digits as its factorization.

20420403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6806804.

The product of its (nonzero) digits is 192, while the sum is 15.

The square root of 20420403 is about 4518.8940018549. The cubic root of 20420403 is about 273.3305044654.

Adding to 20420403 its reverse (30402402), we get a palindrome (50822805).

The spelling of 20420403 in words is "twenty million, four hundred twenty thousand, four hundred three".