21204676 has 24 divisors (see below), whose sum is σ = 38342304. Its totient is φ = 10254720.

The previous prime is 21204641. The next prime is 21204679. The reversal of 21204676 is 67640212.

It is not an unprimeable number, because it can be changed into a prime (21204679) 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, 18891 + ... + 19981.

It is an arithmetic number, because the mean of its divisors is an integer number (1597596).

Almost surely, 2^21204676 is an apocalyptic number.

It is an amenable number.

21204676 is a deficient number, since it is larger than the sum of its proper divisors (17137628).

21204676 is a wasteful number, since it uses less digits than its factorization.

21204676 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1251 (or 1249 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 21204676 is about 4604.8535264436. The cubic root of 21204676 is about 276.7858475896.

Adding to 21204676 its reverse (67640212), we get a palindrome (88844888).

The spelling of 21204676 in words is "twenty-one million, two hundred four thousand, six hundred seventy-six".