21302133 has 4 divisors (see below), whose sum is σ = 28402848. Its totient is φ = 14201420.

The previous prime is 21302129. The next prime is 21302143. The reversal of 21302133 is 33120312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21302133 - 2² = 21302129 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21302123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3550353 + ... + 3550358.

It is an arithmetic number, because the mean of its divisors is an integer number (7100712).

Almost surely, 2^21302133 is an apocalyptic number.

It is an amenable number.

21302133 is a deficient number, since it is larger than the sum of its proper divisors (7100715).

21302133 is an equidigital number, since it uses as much as digits as its factorization.

21302133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7100714.

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 21302133 is about 4615.4233825295. The cubic root of 21302133 is about 277.2092368796.

Adding to 21302133 its reverse (33120312), we get a palindrome (54422445).

The spelling of 21302133 in words is "twenty-one million, three hundred two thousand, one hundred thirty-three".