21104312 has 8 divisors (see below), whose sum is σ = 39570600. Its totient is φ = 10552152.

The previous prime is 21104311. The next prime is 21104323. The reversal of 21104312 is 21340112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21104311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319012 + ... + 1319027.

It is an arithmetic number, because the mean of its divisors is an integer number (4946325).

Almost surely, 2^21104312 is an apocalyptic number.

It is an amenable number.

21104312 is a deficient number, since it is larger than the sum of its proper divisors (18466288).

21104312 is a wasteful number, since it uses less digits than its factorization.

21104312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2638045 (or 2638041 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21104312 is about 4593.9429687361. The cubic root of 21104312 is about 276.3484711365.

Adding to 21104312 its reverse (21340112), we get a palindrome (42444424).

The spelling of 21104312 in words is "twenty-one million, one hundred four thousand, three hundred twelve".