21641303 has 2 divisors, whose sum is σ = 21641304. Its totient is φ = 21641302.

The previous prime is 21641281. The next prime is 21641309. The reversal of 21641303 is 30314612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21641303 - 2⁶ = 21641239 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 (21641309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10820651 + 10820652.

It is an arithmetic number, because the mean of its divisors is an integer number (10820652).

Almost surely, 2^21641303 is an apocalyptic number.

21641303 is a deficient number, since it is larger than the sum of its proper divisors (1).

21641303 is an equidigital number, since it uses as much as digits as its factorization.

21641303 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 21641303 is about 4652.0213886009. The cubic root of 21641303 is about 278.6727276814.

Adding to 21641303 its reverse (30314612), we get a palindrome (51955915).

The spelling of 21641303 in words is "twenty-one million, six hundred forty-one thousand, three hundred three".