21530322133 has 2 divisors, whose sum is σ = 21530322134. Its totient is φ = 21530322132.

The previous prime is 21530322113. The next prime is 21530322157. The reversal of 21530322133 is 33122303512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15330649489 + 6199672644 = 123817^2 + 78738^2 .

It is a cyclic number.

It is not a de Polignac number, because 21530322133 - 2¹³ = 21530313941 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21530322098 and 21530322107.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21530322113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10765161066 + 10765161067.

It is an arithmetic number, because the mean of its divisors is an integer number (10765161067).

Almost surely, 2^21530322133 is an apocalyptic number.

It is an amenable number.

21530322133 is a deficient number, since it is larger than the sum of its proper divisors (1).

21530322133 is an equidigital number, since it uses as much as digits as its factorization.

21530322133 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 25.

Adding to 21530322133 its reverse (33122303512), we get a palindrome (54652625645).

The spelling of 21530322133 in words is "twenty-one billion, five hundred thirty million, three hundred twenty-two thousand, one hundred thirty-three".