21042024 has 16 divisors (see below), whose sum is σ = 52605120. Its totient is φ = 7014000.

The previous prime is 21042017. The next prime is 21042053. The reversal of 21042024 is 42024012.

It is a junction number, because it is equal to n+sod(n) for n = 21041994 and 21042012.

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, 438352 + ... + 438399.

It is an arithmetic number, because the mean of its divisors is an integer number (3287820).

Almost surely, 2^21042024 is an apocalyptic number.

21042024 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21042024 is an abundant number, since it is smaller than the sum of its proper divisors (31563096).

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

21042024 is a wasteful number, since it uses less digits than its factorization.

21042024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876760 (or 876756 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 21042024 is about 4587.1585976506. The cubic root of 21042024 is about 276.0763283957.

Adding to 21042024 its reverse (42024012), we get a palindrome (63066036).

The spelling of 21042024 in words is "twenty-one million, forty-two thousand, twenty-four".