9809765856 has 144 divisors (see below), whose sum is σ = 30475605888. Its totient is φ = 2968454400.

The previous prime is 9809765843. The next prime is 9809765893. The reversal of 9809765856 is 6585679089.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×9809765856² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 9809765793 and 9809765802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2808271 + ... + 2811761.

It is an arithmetic number, because the mean of its divisors is an integer number (211636152).

Almost surely, 2^9809765856 is an apocalyptic number.

9809765856 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9809765856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15237802944).

9809765856 is an abundant number, since it is smaller than the sum of its proper divisors (20665840032).

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

9809765856 is a wasteful number, since it uses less digits than its factorization.

9809765856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4405 (or 4394 counting only the distinct ones).

The product of its (nonzero) digits is 32659200, while the sum is 63.

The square root of 9809765856 is about 99044.2621053840. The cubic root of 9809765856 is about 2140.6855648443.

The spelling of 9809765856 in words is "nine billion, eight hundred nine million, seven hundred sixty-five thousand, eight hundred fifty-six".