21033733 has 8 divisors (see below), whose sum is σ = 24272768. Its totient is φ = 17853264.

The previous prime is 21033721. The next prime is 21033737. The reversal of 21033733 is 33733012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033737) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13866 + ... + 15307.

It is an arithmetic number, because the mean of its divisors is an integer number (3034096).

Almost surely, 2^21033733 is an apocalyptic number.

It is an amenable number.

21033733 is a deficient number, since it is larger than the sum of its proper divisors (3239035).

21033733 is a wasteful number, since it uses less digits than its factorization.

21033733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29283.

The product of its (nonzero) digits is 1134, while the sum is 22.

The square root of 21033733 is about 4586.2547901310. The cubic root of 21033733 is about 276.0400636723.

Adding to 21033733 its reverse (33733012), we get a palindrome (54766745).

The spelling of 21033733 in words is "twenty-one million, thirty-three thousand, seven hundred thirty-three".