9656599681 has 4 divisors (see below), whose sum is σ = 9778835200. Its totient is φ = 9534364164.

The previous prime is 9656599669. The next prime is 9656599723. The reversal of 9656599681 is 1869956569.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 9656599681 - 2¹³ = 9656591489 is a prime.

It is a super-2 number, since 2×9656599681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9656599621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61117641 + ... + 61117798.

It is an arithmetic number, because the mean of its divisors is an integer number (2444708800).

Almost surely, 2^9656599681 is an apocalyptic number.

It is an amenable number.

9656599681 is a deficient number, since it is larger than the sum of its proper divisors (122235519).

9656599681 is a wasteful number, since it uses less digits than its factorization.

9656599681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122235518.

The product of its digits is 31492800, while the sum is 64.

The square root of 9656599681 is about 98267.9992723979. Note that the first 3 decimals coincide. The cubic root of 9656599681 is about 2129.4857715931.

The spelling of 9656599681 in words is "nine billion, six hundred fifty-six million, five hundred ninety-nine thousand, six hundred eighty-one".