21530050189 has 2 divisors, whose sum is σ = 21530050190. Its totient is φ = 21530050188.

The previous prime is 21530050181. The next prime is 21530050237. The reversal of 21530050189 is 98105003512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14700350025 + 6829700164 = 121245^2 + 82642^2 .

It is a cyclic number.

It is not a de Polignac number, because 21530050189 - 2³ = 21530050181 is a prime.

It is a super-2 number, since 2×21530050189² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21530050181) 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, 10765025094 + 10765025095.

It is an arithmetic number, because the mean of its divisors is an integer number (10765025095).

Almost surely, 2^21530050189 is an apocalyptic number.

It is an amenable number.

21530050189 is a deficient number, since it is larger than the sum of its proper divisors (1).

21530050189 is an equidigital number, since it uses as much as digits as its factorization.

21530050189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 34.

The spelling of 21530050189 in words is "twenty-one billion, five hundred thirty million, fifty thousand, one hundred eighty-nine".