21530105707732 has 6 divisors (see below), whose sum is σ = 37677684988538. Its totient is φ = 10765052853864.

The previous prime is 21530105707711. The next prime is 21530105707769. The reversal of 21530105707732 is 23770750103512.

It can be written as a sum of positive squares in only one way, i.e., 11476348680976 + 10053757026756 = 3387676^2 + 3170766^2 .

It is a super-2 number, since 2×21530105707732² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2691263213463 + ... + 2691263213470.

Almost surely, 2^{21530105707732} is an apocalyptic number.

It is an amenable number.

21530105707732 is a deficient number, since it is larger than the sum of its proper divisors (16147579280806).

21530105707732 is a wasteful number, since it uses less digits than its factorization.

21530105707732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5382526426937 (or 5382526426935 counting only the distinct ones).

The product of its (nonzero) digits is 308700, while the sum is 43.

The spelling of 21530105707732 in words is "twenty-one trillion, five hundred thirty billion, one hundred five million, seven hundred seven thousand, seven hundred thirty-two".