21470203 has 4 divisors (see below), whose sum is σ = 21481488. Its totient is φ = 21458920.

The previous prime is 21470149. The next prime is 21470219. The reversal of 21470203 is 30207412.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21470203 is a prime.

It is a super-3 number, since 3×21470203³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21470233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2008 + ... + 6853.

It is an arithmetic number, because the mean of its divisors is an integer number (5370372).

Almost surely, 2^21470203 is an apocalyptic number.

21470203 is a deficient number, since it is larger than the sum of its proper divisors (11285).

21470203 is an equidigital number, since it uses as much as digits as its factorization.

21470203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11284.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 21470203 is about 4633.5950405706. The cubic root of 21470203 is about 277.9363715808.

Adding to 21470203 its reverse (30207412), we get a palindrome (51677615).

The spelling of 21470203 in words is "twenty-one million, four hundred seventy thousand, two hundred three".