21358219 has 2 divisors, whose sum is σ = 21358220. Its totient is φ = 21358218.

The previous prime is 21358201. The next prime is 21358241. The reversal of 21358219 is 91285312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21358219 - 2⁵ = 21358187 is a prime.

It is a super-2 number, since 2×21358219² = 912347037703922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21358289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10679109 + 10679110.

It is an arithmetic number, because the mean of its divisors is an integer number (10679110).

Almost surely, 2^21358219 is an apocalyptic number.

21358219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21358219 is an equidigital number, since it uses as much as digits as its factorization.

21358219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4320, while the sum is 31.

The square root of 21358219 is about 4621.4953207809. The cubic root of 21358219 is about 277.4523100689.

The spelling of 21358219 in words is "twenty-one million, three hundred fifty-eight thousand, two hundred nineteen".