21361303 has 2 divisors, whose sum is σ = 21361304. Its totient is φ = 21361302.

The previous prime is 21361283. The next prime is 21361391. The reversal of 21361303 is 30316312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21361303 - 2⁵ = 21361271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21361003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10680651 + 10680652.

It is an arithmetic number, because the mean of its divisors is an integer number (10680652).

Almost surely, 2^21361303 is an apocalyptic number.

21361303 is a deficient number, since it is larger than the sum of its proper divisors (1).

21361303 is an equidigital number, since it uses as much as digits as its factorization.

21361303 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 19.

The square root of 21361303 is about 4621.8289669783. The cubic root of 21361303 is about 277.4656635816.

Adding to 21361303 its reverse (30316312), we get a palindrome (51677615).

It can be divided in two parts, 213 and 61303, that added together give a palindrome (61516).

The spelling of 21361303 in words is "twenty-one million, three hundred sixty-one thousand, three hundred three".