21024312 has 16 divisors (see below), whose sum is σ = 52560840. Its totient is φ = 7008096.

The previous prime is 21024299. The next prime is 21024313. The reversal of 21024312 is 21342012.

It is a junction number, because it is equal to n+sod(n) for n = 21024291 and 21024300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21024313) 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, 437983 + ... + 438030.

Almost surely, 2^21024312 is an apocalyptic number.

It is an amenable number.

21024312 is an abundant number, since it is smaller than the sum of its proper divisors (31536528).

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

21024312 is a wasteful number, since it uses less digits than its factorization.

21024312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876022 (or 876018 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21024312 is about 4585.2275843190. The cubic root of 21024312 is about 275.9988447757.

Adding to 21024312 its reverse (21342012), we get a palindrome (42366324).

The spelling of 21024312 in words is "twenty-one million, twenty-four thousand, three hundred twelve".