21505332203 has 2 divisors, whose sum is σ = 21505332204. Its totient is φ = 21505332202.

The previous prime is 21505332193. The next prime is 21505332227. The reversal of 21505332203 is 30223350512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21505332203 - 2¹⁶ = 21505266667 is a prime.

It is a super-2 number, since 2×21505332203² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21505332703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10752666101 + 10752666102.

It is an arithmetic number, because the mean of its divisors is an integer number (10752666102).

Almost surely, 2^21505332203 is an apocalyptic number.

21505332203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21505332203 is an equidigital number, since it uses as much as digits as its factorization.

21505332203 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 26.

Adding to 21505332203 its reverse (30223350512), we get a palindrome (51728682715).

The spelling of 21505332203 in words is "twenty-one billion, five hundred five million, three hundred thirty-two thousand, two hundred three".