21103004 has 12 divisors (see below), whose sum is σ = 39771144. Its totient is φ = 9739824.

The previous prime is 21103003. The next prime is 21103021. The reversal of 21103004 is 40030112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202862 + ... + 202965.

It is an arithmetic number, because the mean of its divisors is an integer number (3314262).

Almost surely, 2^21103004 is an apocalyptic number.

It is an amenable number.

21103004 is a deficient number, since it is larger than the sum of its proper divisors (18668140).

21103004 is a wasteful number, since it uses less digits than its factorization.

21103004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405844 (or 405842 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 21103004 is about 4593.8006051634. The cubic root of 21103004 is about 276.3427618567.

Adding to 21103004 its reverse (40030112), we get a palindrome (61133116).

The spelling of 21103004 in words is "twenty-one million, one hundred three thousand, four".