21416203 has 4 divisors (see below), whose sum is σ = 21484080. Its totient is φ = 21348328.

The previous prime is 21416183. The next prime is 21416281. The reversal of 21416203 is 30261412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21416203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21416503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33463 + ... + 34096.

It is an arithmetic number, because the mean of its divisors is an integer number (5371020).

Almost surely, 2^21416203 is an apocalyptic number.

21416203 is a deficient number, since it is larger than the sum of its proper divisors (67877).

21416203 is an equidigital number, since it uses as much as digits as its factorization.

21416203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67876.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21416203 is about 4627.7643630591. The cubic root of 21416203 is about 277.7031621040.

Adding to 21416203 its reverse (30261412), we get a palindrome (51677615).

The spelling of 21416203 in words is "twenty-one million, four hundred sixteen thousand, two hundred three".