21530535052145 has 16 divisors (see below), whose sum is σ = 29968301244288. Its totient is φ = 14543440306560.

The previous prime is 21530535052129. The next prime is 21530535052151. The reversal of 21530535052145 is 54125053503512.

It is not a de Polignac number, because 21530535052145 - 2⁴ = 21530535052129 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4590730076 + ... + 4590734765.

It is an arithmetic number, because the mean of its divisors is an integer number (1873018827768).

Almost surely, 2^{21530535052145} is an apocalyptic number.

It is an amenable number.

21530535052145 is a deficient number, since it is larger than the sum of its proper divisors (8437766192143).

21530535052145 is an equidigital number, since it uses as much as digits as its factorization.

21530535052145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9181464920.

The product of its (nonzero) digits is 450000, while the sum is 41.

Adding to 21530535052145 its reverse (54125053503512), we get a palindrome (75655588555657).

The spelling of 21530535052145 in words is "twenty-one trillion, five hundred thirty billion, five hundred thirty-five million, fifty-two thousand, one hundred forty-five".