13135352721 has 32 divisors (see below), whose sum is σ = 18117485568. Its totient is φ = 8458732800.

The previous prime is 13135352653. The next prime is 13135352729. The reversal of 13135352721 is 12725353131.

It is not a de Polignac number, because 13135352721 - 2¹¹ = 13135350673 is a prime.

It is a super-2 number, since 2×13135352721² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13135352729) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17351475 + ... + 17352231.

It is an arithmetic number, because the mean of its divisors is an integer number (566171424).

Almost surely, 2^13135352721 is an apocalyptic number.

It is an amenable number.

13135352721 is a deficient number, since it is larger than the sum of its proper divisors (4982132847).

13135352721 is a wasteful number, since it uses less digits than its factorization.

13135352721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1721.

The product of its digits is 18900, while the sum is 33.

The spelling of 13135352721 in words is "thirteen billion, one hundred thirty-five million, three hundred fifty-two thousand, seven hundred twenty-one".