21124315 has 8 divisors (see below), whose sum is σ = 25387920. Its totient is φ = 16873632.

The previous prime is 21124289. The next prime is 21124321. The reversal of 21124315 is 51342112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21124315 - 2¹¹ = 21122267 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21124292 and 21124301.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 837 + ... + 6553.

It is an arithmetic number, because the mean of its divisors is an integer number (3173490).

Almost surely, 2^21124315 is an apocalyptic number.

21124315 is a deficient number, since it is larger than the sum of its proper divisors (4263605).

21124315 is an equidigital number, since it uses as much as digits as its factorization.

21124315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6461.

The product of its digits is 240, while the sum is 19.

The square root of 21124315 is about 4596.1195589323. The cubic root of 21124315 is about 276.4357527142.

Adding to 21124315 its reverse (51342112), we get a palindrome (72466427).

The spelling of 21124315 in words is "twenty-one million, one hundred twenty-four thousand, three hundred fifteen".