21124312 has 16 divisors (see below), whose sum is σ = 43209000. Its totient is φ = 9601920.

The previous prime is 21124289. The next prime is 21124321. The reversal of 21124312 is 21342112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119937 + ... + 120112.

Almost surely, 2^21124312 is an apocalyptic number.

21124312 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21124312 is an abundant number, since it is smaller than the sum of its proper divisors (22084688).

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

21124312 is a wasteful number, since it uses less digits than its factorization.

21124312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240066 (or 240062 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 21124312 is about 4596.1192325700. The cubic root of 21124312 is about 276.4357396280.

Adding to 21124312 its reverse (21342112), we get a palindrome (42466424).

The spelling of 21124312 in words is "twenty-one million, one hundred twenty-four thousand, three hundred twelve".