21245104 has 40 divisors (see below), whose sum is σ = 44782848. Its totient is φ = 9722880.

The previous prime is 21245099. The next prime is 21245111. The reversal of 21245104 is 40154212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9009 + ... + 11119.

Almost surely, 2^21245104 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21245104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22391424).

21245104 is an abundant number, since it is smaller than the sum of its proper divisors (23537744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21245104 is a wasteful number, since it uses less digits than its factorization.

21245104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2173 (or 2167 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 21245104 is about 4609.2411522939. The cubic root of 21245104 is about 276.9616389161.

Adding to 21245104 its reverse (40154212), we get a palindrome (61399316).

The spelling of 21245104 in words is "twenty-one million, two hundred forty-five thousand, one hundred four".