21133291 has 2 divisors, whose sum is σ = 21133292. Its totient is φ = 21133290.

The previous prime is 21133283. The next prime is 21133303. The reversal of 21133291 is 19233112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21133291 - 2³ = 21133283 is a prime.

It is not a weakly prime, because it can be changed into another prime (21133241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566645 + 10566646.

It is an arithmetic number, because the mean of its divisors is an integer number (10566646).

Almost surely, 2^21133291 is an apocalyptic number.

21133291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133291 is an equidigital number, since it uses as much as digits as its factorization.

21133291 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 324, while the sum is 22.

The square root of 21133291 is about 4597.0959311287. The cubic root of 21133291 is about 276.4749009020.

The spelling of 21133291 in words is "twenty-one million, one hundred thirty-three thousand, two hundred ninety-one".