21160521331465 has 8 divisors (see below), whose sum is σ = 25539403781448. Its totient is φ = 16830564942720.

The previous prime is 21160521331427. The next prime is 21160521331471. The reversal of 21160521331465 is 56413312506112.

It can be written as a sum of positive squares in 4 ways, for example, as 9672977039881 + 11487544291584 = 3110141^2 + 3389328^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21160521331465 - 2¹¹ = 21160521329417 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12231514356 + ... + 12231516085.

It is an arithmetic number, because the mean of its divisors is an integer number (3192425472681).

Almost surely, 2^{21160521331465} is an apocalyptic number.

It is an amenable number.

21160521331465 is a deficient number, since it is larger than the sum of its proper divisors (4378882449983).

21160521331465 is a wasteful number, since it uses less digits than its factorization.

21160521331465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24463030619.

The product of its (nonzero) digits is 129600, while the sum is 40.

Adding to 21160521331465 its reverse (56413312506112), we get a palindrome (77573833837577).

The spelling of 21160521331465 in words is "twenty-one trillion, one hundred sixty billion, five hundred twenty-one million, three hundred thirty-one thousand, four hundred sixty-five".