21243103 has 8 divisors (see below), whose sum is σ = 24571008. Its totient is φ = 17988504.

The previous prime is 21243077. The next prime is 21243137. The reversal of 21243103 is 30134212.

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 21243103 - 2⁹ = 21242591 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243193) 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, 17701 + ... + 18862.

It is an arithmetic number, because the mean of its divisors is an integer number (3071376).

Almost surely, 2^21243103 is an apocalyptic number.

21243103 is a deficient number, since it is larger than the sum of its proper divisors (3327905).

21243103 is an equidigital number, since it uses as much as digits as its factorization.

21243103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36653.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21243103 is about 4609.0240832523. The cubic root of 21243103 is about 276.9529433026.

Adding to 21243103 its reverse (30134212), we get a palindrome (51377315).

The spelling of 21243103 in words is "twenty-one million, two hundred forty-three thousand, one hundred three".