21307036 has 6 divisors (see below), whose sum is σ = 37287320. Its totient is φ = 10653516.

The previous prime is 21306997. The next prime is 21307043. The reversal of 21307036 is 63070312.

It is a junction number, because it is equal to n+sod(n) for n = 21306998 and 21307016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2663376 + ... + 2663383.

Almost surely, 2^21307036 is an apocalyptic number.

It is an amenable number.

21307036 is a deficient number, since it is larger than the sum of its proper divisors (15980284).

21307036 is a wasteful number, since it uses less digits than its factorization.

21307036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5326763 (or 5326761 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 22.

The square root of 21307036 is about 4615.9545058417. The cubic root of 21307036 is about 277.2305031791.

Adding to 21307036 its reverse (63070312), we get a palindrome (84377348).

The spelling of 21307036 in words is "twenty-one million, three hundred seven thousand, thirty-six".