21203103 has 8 divisors (see below), whose sum is σ = 28302768. Its totient is φ = 14119424.

The previous prime is 21203099. The next prime is 21203113. The reversal of 21203103 is 30130212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21203103 - 2² = 21203099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 450 + ... + 6527.

It is an arithmetic number, because the mean of its divisors is an integer number (3537846).

Almost surely, 2^21203103 is an apocalyptic number.

21203103 is a deficient number, since it is larger than the sum of its proper divisors (7099665).

21203103 is a wasteful number, since it uses less digits than its factorization.

21203103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7993.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21203103 is about 4604.6827252266. The cubic root of 21203103 is about 276.7790032674.

Adding to 21203103 its reverse (30130212), we get a palindrome (51333315).

The spelling of 21203103 in words is "twenty-one million, two hundred three thousand, one hundred three".