21113203 has 8 divisors (see below), whose sum is σ = 21500640. Its totient is φ = 20729280.

The previous prime is 21113173. The next prime is 21113221. The reversal of 21113203 is 30231112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21113243) 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 7 ways as a sum of consecutive naturals, for example, 13218 + ... + 14728.

It is an arithmetic number, because the mean of its divisors is an integer number (2687580).

Almost surely, 2^21113203 is an apocalyptic number.

21113203 is a deficient number, since it is larger than the sum of its proper divisors (387437).

21113203 is a wasteful number, since it uses less digits than its factorization.

21113203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1757.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 21113203 is about 4594.9105540805. The cubic root of 21113203 is about 276.3872731485.

Adding to 21113203 its reverse (30231112), we get a palindrome (51344315).

It can be divided in two parts, 21113 and 203, that added together give a square (21316 = 146²).

The spelling of 21113203 in words is "twenty-one million, one hundred thirteen thousand, two hundred three".