21128183 has 2 divisors, whose sum is σ = 21128184. Its totient is φ = 21128182.

The previous prime is 21128167. The next prime is 21128189. The reversal of 21128183 is 38182112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21128183 - 2⁴ = 21128167 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21128189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10564091 + 10564092.

It is an arithmetic number, because the mean of its divisors is an integer number (10564092).

Almost surely, 2^21128183 is an apocalyptic number.

21128183 is a deficient number, since it is larger than the sum of its proper divisors (1).

21128183 is an equidigital number, since it uses as much as digits as its factorization.

21128183 is an evil number, because the sum of its binary digits is even.

The product of its digits is 768, while the sum is 26.

The square root of 21128183 is about 4596.5403294217. The cubic root of 21128183 is about 276.4526240815.

The spelling of 21128183 in words is "twenty-one million, one hundred twenty-eight thousand, one hundred eighty-three".