21442203 has 24 divisors (see below), whose sum is σ = 33493200. Its totient is φ = 13172544.

The previous prime is 21442163. The next prime is 21442229. The reversal of 21442203 is 30224412.

21442203 is a `hidden beast` number, since 21 + 442 + 203 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-21442203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21442243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4633 + ... + 8021.

It is an arithmetic number, because the mean of its divisors is an integer number (1395550).

Almost surely, 2^21442203 is an apocalyptic number.

21442203 is a deficient number, since it is larger than the sum of its proper divisors (12050997).

21442203 is a wasteful number, since it uses less digits than its factorization.

21442203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3451 (or 3448 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 21442203 is about 4630.5726427732. The cubic root of 21442203 is about 277.8154970231.

Adding to 21442203 its reverse (30224412), we get a palindrome (51666615).

The spelling of 21442203 in words is "twenty-one million, four hundred forty-two thousand, two hundred three".