8521646400 has 252 divisors, whose sum is σ = 30561812892. Its totient is φ = 2251898880.

The previous prime is 8521646383. The next prime is 8521646407. The reversal of 8521646400 is 46461258.

8521646400 is a `hidden beast` number, since 8 + 5 + 2 + 1 + 6 + 4 + 640 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 606341376 + 7915305024 = 24624^2 + 88968^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8521646407) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1624582 + ... + 1629818.

Almost surely, 2^8521646400 is an apocalyptic number.

8521646400 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 8521646400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15280906446).

8521646400 is an abundant number, since it is smaller than the sum of its proper divisors (22040166492).

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

8521646400 is a wasteful number, since it uses less digits than its factorization.

8521646400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5378 (or 5360 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 8521646400 is about 92312.7640145175. The cubic root of 8521646400 is about 2042.5584969166.

The spelling of 8521646400 in words is "eight billion, five hundred twenty-one million, six hundred forty-six thousand, four hundred".