21532532121065 has 32 divisors (see below), whose sum is σ = 30599576494080. Its totient is φ = 14239234586304.

The previous prime is 21532532121049. The next prime is 21532532121091. The reversal of 21532532121065 is 56012123523512.

It is not a de Polignac number, because 21532532121065 - 2⁴ = 21532532121049 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90433829 + ... + 90671618.

It is an arithmetic number, because the mean of its divisors is an integer number (956236765440).

Almost surely, 2^{21532532121065} is an apocalyptic number.

It is an amenable number.

21532532121065 is a deficient number, since it is larger than the sum of its proper divisors (9067044373015).

21532532121065 is a wasteful number, since it uses less digits than its factorization.

21532532121065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181105581.

The product of its (nonzero) digits is 108000, while the sum is 38.

Adding to 21532532121065 its reverse (56012123523512), we get a palindrome (77544655644577).

The spelling of 21532532121065 in words is "twenty-one trillion, five hundred thirty-two billion, five hundred thirty-two million, one hundred twenty-one thousand, sixty-five".