20530403 has 4 divisors (see below), whose sum is σ = 20540688. Its totient is φ = 20520120.

The previous prime is 20530397. The next prime is 20530417. The reversal of 20530403 is 30403502.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 30403502 = 2 ⋅15201751.

It is a cyclic number.

It is not a de Polignac number, because 20530403 - 2¹² = 20526307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20530423) 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, 1076 + ... + 6497.

It is an arithmetic number, because the mean of its divisors is an integer number (5135172).

Almost surely, 2^20530403 is an apocalyptic number.

20530403 is a deficient number, since it is larger than the sum of its proper divisors (10285).

20530403 is an equidigital number, since it uses as much as digits as its factorization.

20530403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10284.

The product of its (nonzero) digits is 360, while the sum is 17.

The square root of 20530403 is about 4531.0487748423. The cubic root of 20530403 is about 273.8204152936.

Adding to 20530403 its reverse (30403502), we get a palindrome (50933905).

The spelling of 20530403 in words is "twenty million, five hundred thirty thousand, four hundred three".