21031133 has 8 divisors (see below), whose sum is σ = 21769440. Its totient is φ = 20301840.

The previous prime is 21031111. The next prime is 21031151. The reversal of 21031133 is 33113012.

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

It is a cyclic number.

It is not a de Polignac number, because 21031133 - 2¹⁰ = 21030109 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 (21031103) 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, 2678 + ... + 7016.

It is an arithmetic number, because the mean of its divisors is an integer number (2721180).

Almost surely, 2^21031133 is an apocalyptic number.

It is an amenable number.

21031133 is a deficient number, since it is larger than the sum of its proper divisors (738307).

21031133 is a wasteful number, since it uses less digits than its factorization.

21031133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4507.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 21031133 is about 4585.9713256845. The cubic root of 21031133 is about 276.0286893443.

Adding to 21031133 its reverse (33113012), we get a palindrome (54144145).

The spelling of 21031133 in words is "twenty-one million, thirty-one thousand, one hundred thirty-three".