21530243183 has 2 divisors, whose sum is σ = 21530243184. Its totient is φ = 21530243182.

The previous prime is 21530243177. The next prime is 21530243221. The reversal of 21530243183 is 38134203512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21530243183 - 2⁸ = 21530242927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21530243143) 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, 10765121591 + 10765121592.

It is an arithmetic number, because the mean of its divisors is an integer number (10765121592).

Almost surely, 2^21530243183 is an apocalyptic number.

21530243183 is a deficient number, since it is larger than the sum of its proper divisors (1).

21530243183 is an equidigital number, since it uses as much as digits as its factorization.

21530243183 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17280, while the sum is 32.

Adding to 21530243183 its reverse (38134203512), we get a palindrome (59664446695).

The spelling of 21530243183 in words is "twenty-one billion, five hundred thirty million, two hundred forty-three thousand, one hundred eighty-three".