21231133 has 8 divisors (see below), whose sum is σ = 26470080. Its totient is φ = 16543680.

The previous prime is 21231107. The next prime is 21231143. The reversal of 21231133 is 33113212.

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-21231133 is a prime.

It is a super-2 number, since 2×21231133² = 901522016927378, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231143) 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, 137788 + ... + 137941.

It is an arithmetic number, because the mean of its divisors is an integer number (3308760).

Almost surely, 2^21231133 is an apocalyptic number.

It is an amenable number.

21231133 is a deficient number, since it is larger than the sum of its proper divisors (5238947).

21231133 is a wasteful number, since it uses less digits than its factorization.

21231133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275747.

The product of its digits is 108, while the sum is 16.

The square root of 21231133 is about 4607.7253607393. The cubic root of 21231133 is about 276.9009146576.

Adding to 21231133 its reverse (33113212), we get a palindrome (54344345).

The spelling of 21231133 in words is "twenty-one million, two hundred thirty-one thousand, one hundred thirty-three".