21534328 has 16 divisors (see below), whose sum is σ = 40519080. Its totient is φ = 10729248.

The previous prime is 21534323. The next prime is 21534329. The reversal of 21534328 is 82343512.

It is a junction number, because it is equal to n+sod(n) for n = 21534296 and 21534305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21534323) 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, 2250 + ... + 6937.

Almost surely, 2^21534328 is an apocalyptic number.

It is an amenable number.

21534328 is a deficient number, since it is larger than the sum of its proper divisors (18984752).

21534328 is a wasteful number, since it uses less digits than its factorization.

21534328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9486 (or 9482 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

The square root of 21534328 is about 4640.5094547905. The cubic root of 21534328 is about 278.2128005083.

It can be divided in two parts, 215 and 34328, that added together give a palindrome (34543).

The spelling of 21534328 in words is "twenty-one million, five hundred thirty-four thousand, three hundred twenty-eight".