9961645831 has 8 divisors (see below), whose sum is σ = 10487664000. Its totient is φ = 9435799800.

The previous prime is 9961645829. The next prime is 9961645847. The reversal of 9961645831 is 1385461699.

9961645831 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 9961645831 - 2¹ = 9961645829 is a prime.

It is a super-2 number, since 2×9961645831² (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 (9961645861) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85656 + ... + 165106.

It is an arithmetic number, because the mean of its divisors is an integer number (1310958000).

Almost surely, 2^9961645831 is an apocalyptic number.

9961645831 is a deficient number, since it is larger than the sum of its proper divisors (526018169).

9961645831 is a wasteful number, since it uses less digits than its factorization.

9961645831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86069.

The product of its digits is 1399680, while the sum is 52.

The square root of 9961645831 is about 99808.0449212387. The cubic root of 9961645831 is about 2151.6767760309.

The spelling of 9961645831 in words is "nine billion, nine hundred sixty-one million, six hundred forty-five thousand, eight hundred thirty-one".