21203450 has 24 divisors (see below), whose sum is σ = 39655200. Its totient is φ = 8434800.

The previous prime is 21203431. The next prime is 21203459. The reversal of 21203450 is 5430212.

It is not an unprimeable number, because it can be changed into a prime (21203459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8885 + ... + 11015.

It is an arithmetic number, because the mean of its divisors is an integer number (1652300).

Almost surely, 2^21203450 is an apocalyptic number.

21203450 is a deficient number, since it is larger than the sum of its proper divisors (18451750).

21203450 is a wasteful number, since it uses less digits than its factorization.

21203450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2342 (or 2337 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 21203450 is about 4604.7204041071. The cubic root of 21203450 is about 276.7805131375.

Adding to 21203450 its reverse (5430212), we get a palindrome (26633662).

The spelling of 21203450 in words is "twenty-one million, two hundred three thousand, four hundred fifty".