9661659439040 has 112 divisors (see below), whose sum is σ = 26294987930112. Its totient is φ = 3312383517696.

The previous prime is 9661659439001. The next prime is 9661659439057. The reversal of 9661659439040 is 409349561669.

9661659439040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 3108321²-1.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×9661659439040² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43405469 + ... + 43627491.

Almost surely, 2^{9661659439040} is an apocalyptic number.

It is an amenable number.

9661659439040 is an abundant number, since it is smaller than the sum of its proper divisors (16633328491072).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9661659439040 is a wasteful number, since it uses less digits than its factorization.

9661659439040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241474 (or 241464 counting only the distinct ones).

The product of its (nonzero) digits is 37791360, while the sum is 62.

The spelling of 9661659439040 in words is "nine trillion, six hundred sixty-one billion, six hundred fifty-nine million, four hundred thirty-nine thousand, forty".