21024434 has 8 divisors (see below), whose sum is σ = 31598748. Its totient is φ = 10491520.

The previous prime is 21024433. The next prime is 21024457. The reversal of 21024434 is 43442012.

It can be written as a sum of positive squares in 2 ways, for example, as 21022225 + 2209 = 4585^2 + 47^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21024433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9047 + ... + 11130.

Almost surely, 2^21024434 is an apocalyptic number.

21024434 is a deficient number, since it is larger than the sum of its proper divisors (10574314).

21024434 is a wasteful number, since it uses less digits than its factorization.

21024434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20700.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 21024434 is about 4585.2408878924. The cubic root of 21024434 is about 275.9993786305. Note that the first 3 decimals are identical.

Adding to 21024434 its reverse (43442012), we get a palindrome (64466446).

The spelling of 21024434 in words is "twenty-one million, twenty-four thousand, four hundred thirty-four".