21938183 has 2 divisors, whose sum is σ = 21938184. Its totient is φ = 21938182.

The previous prime is 21938167. The next prime is 21938197. The reversal of 21938183 is 38183912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21938183 - 2⁴ = 21938167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21938083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10969091 + 10969092.

It is an arithmetic number, because the mean of its divisors is an integer number (10969092).

Almost surely, 2^21938183 is an apocalyptic number.

21938183 is a deficient number, since it is larger than the sum of its proper divisors (1).

21938183 is an equidigital number, since it uses as much as digits as its factorization.

21938183 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 35.

The square root of 21938183 is about 4683.8214099173. The cubic root of 21938183 is about 279.9412419222.

The spelling of 21938183 in words is "twenty-one million, nine hundred thirty-eight thousand, one hundred eighty-three".