9956521613 has 4 divisors (see below), whose sum is σ = 9963209820. Its totient is φ = 9949833408.

The previous prime is 9956521571. The next prime is 9956521621. The reversal of 9956521613 is 3161256599.

9956521613 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4668032329 + 5288489284 = 68323^2 + 72722^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9956521613 is a prime.

It is a super-2 number, since 2×9956521613² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9956521693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3341870 + ... + 3344847.

It is an arithmetic number, because the mean of its divisors is an integer number (2490802455).

Almost surely, 2^9956521613 is an apocalyptic number.

It is an amenable number.

9956521613 is a deficient number, since it is larger than the sum of its proper divisors (6688207).

9956521613 is a wasteful number, since it uses less digits than its factorization.

9956521613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6688206.

The product of its digits is 437400, while the sum is 47.

The square root of 9956521613 is about 99782.3712536438. The cubic root of 9956521613 is about 2151.3077756968.

The spelling of 9956521613 in words is "nine billion, nine hundred fifty-six million, five hundred twenty-one thousand, six hundred thirteen".