21230003 has 4 divisors (see below), whose sum is σ = 21723768. Its totient is φ = 20736240.

The previous prime is 21229979. The next prime is 21230017. The reversal of 21230003 is 30003212.

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 21230003 - 2¹⁰ = 21228979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21230023) 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, 246818 + ... + 246903.

It is an arithmetic number, because the mean of its divisors is an integer number (5430942).

Almost surely, 2^21230003 is an apocalyptic number.

21230003 is a deficient number, since it is larger than the sum of its proper divisors (493765).

21230003 is an equidigital number, since it uses as much as digits as its factorization.

21230003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493764.

The product of its (nonzero) digits is 36, while the sum is 11.

The square root of 21230003 is about 4607.6027389522. The cubic root of 21230003 is about 276.8960020043.

Adding to 21230003 its reverse (30003212), we get a palindrome (51233215).

It can be divided in two parts, 212 and 30003, that multiplied together give a palindrome (6360636).

The spelling of 21230003 in words is "twenty-one million, two hundred thirty thousand, three".