21315004 has 12 divisors (see below), whose sum is σ = 37457728. Its totient is φ = 10612800.

The previous prime is 21315001. The next prime is 21315013. The reversal of 21315004 is 40051312.

It is a hoax number, since the sum of its digits (16) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21315001) 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, 10092 + ... + 12019.

Almost surely, 2^21315004 is an apocalyptic number.

It is an amenable number.

21315004 is a deficient number, since it is larger than the sum of its proper divisors (16142724).

21315004 is a wasteful number, since it uses less digits than its factorization.

21315004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22356 (or 22354 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21315004 is about 4616.8175185944. The cubic root of 21315004 is about 277.2650566689.

Adding to 21315004 its reverse (40051312), we get a palindrome (61366316).

The spelling of 21315004 in words is "twenty-one million, three hundred fifteen thousand, four".