21533339 has 8 divisors (see below), whose sum is σ = 22845888. Its totient is φ = 20225920.

The previous prime is 21533333. The next prime is 21533357. The reversal of 21533339 is 93333512.

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

It is a de Polignac number, because none of the positive numbers 2^k-21533339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21533333) 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 7 ways as a sum of consecutive naturals, for example, 10574 + ... + 12444.

It is an arithmetic number, because the mean of its divisors is an integer number (2855736).

Almost surely, 2^21533339 is an apocalyptic number.

21533339 is a deficient number, since it is larger than the sum of its proper divisors (1312549).

21533339 is a wasteful number, since it uses less digits than its factorization.

21533339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2565.

The product of its digits is 7290, while the sum is 29.

The square root of 21533339 is about 4640.4028919912. The cubic root of 21533339 is about 278.2085413139.

The spelling of 21533339 in words is "twenty-one million, five hundred thirty-three thousand, three hundred thirty-nine".