9805555664 has 40 divisors (see below), whose sum is σ = 20122727688. Its totient is φ = 4612792320.

The previous prime is 9805555637. The next prime is 9805555667. The reversal of 9805555664 is 4665555089.

It can be written as a sum of positive squares in 4 ways, for example, as 271986064 + 9533569600 = 16492^2 + 97640^2 .

It is a super-2 number, since 2×9805555664² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9805555667) 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, 1262834 + ... + 1270574.

Almost surely, 2^9805555664 is an apocalyptic number.

It is an amenable number.

9805555664 is an abundant number, since it is smaller than the sum of its proper divisors (10317172024).

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

9805555664 is a wasteful number, since it uses less digits than its factorization.

9805555664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12423 (or 12417 counting only the distinct ones).

The product of its (nonzero) digits is 6480000, while the sum is 53.

The square root of 9805555664 is about 99023.0057309916. The cubic root of 9805555664 is about 2140.3792718758.

The spelling of 9805555664 in words is "nine billion, eight hundred five million, five hundred fifty-five thousand, six hundred sixty-four".