521540008 has 96 divisors (see below), whose sum is σ = 1167362280. Its totient is φ = 217395200.

The previous prime is 521540003. The next prime is 521540023. The reversal of 521540008 is 800045125.

It can be written as a sum of positive squares in 4 ways, for example, as 257217444 + 264322564 = 16038^2 + 16258^2 .

It is not an unprimeable number, because it can be changed into a prime (521540003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 674310 + ... + 675082.

Almost surely, 2^521540008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521540008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (583681140).

521540008 is an abundant number, since it is smaller than the sum of its proper divisors (645822272).

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

521540008 is a wasteful number, since it uses less digits than its factorization.

521540008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 859 (or 844 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 521540008 is about 22837.2504474597. The cubic root of 521540008 is about 804.9382090606.

The spelling of 521540008 in words is "five hundred twenty-one million, five hundred forty thousand, eight".