21104212 has 12 divisors (see below), whose sum is σ = 38876320. Its totient is φ = 9996696.

The previous prime is 21104203. The next prime is 21104221. The reversal of 21104212 is 21240112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21104203) and next prime (21104221).

It is a plaindrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 21104192 and 21104201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138768 + ... + 138919.

Almost surely, 2^21104212 is an apocalyptic number.

It is an amenable number.

21104212 is a deficient number, since it is larger than the sum of its proper divisors (17772108).

21104212 is a wasteful number, since it uses less digits than its factorization.

21104212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277710 (or 277708 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 21104212 is about 4593.9320848267. The cubic root of 21104212 is about 276.3480346555.

Adding to 21104212 its reverse (21240112), we get a palindrome (42344324).

It can be divided in two parts, 21104 and 212, that added together give a square (21316 = 146²).

The spelling of 21104212 in words is "twenty-one million, one hundred four thousand, two hundred twelve".