8505136640 has 320 divisors, whose sum is σ = 27388247040. Its totient is φ = 2446295040.

The previous prime is 8505136639. The next prime is 8505136643. The reversal of 8505136640 is 466315058.

It is a tau number, because it is divible by the number of its divisors (320).

It is a junction number, because it is equal to n+sod(n) for n = 8505136594 and 8505136603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8505136643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2560901 + ... + 2564219.

It is an arithmetic number, because the mean of its divisors is an integer number (85588272).

Almost surely, 2^8505136640 is an apocalyptic number.

8505136640 is a gapful number since it is divisible by the number (80) 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 8505136640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13694123520).

8505136640 is an abundant number, since it is smaller than the sum of its proper divisors (18883110400).

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

8505136640 is a wasteful number, since it uses less digits than its factorization.

8505136640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3373 (or 3357 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 38.

The square root of 8505136640 is about 92223.2977072497. The cubic root of 8505136640 is about 2041.2385660755.

The spelling of 8505136640 in words is "eight billion, five hundred five million, one hundred thirty-six thousand, six hundred forty".