521475840 has 288 divisors, whose sum is σ = 1883750400. Its totient is φ = 136581120.

The previous prime is 521475811. The next prime is 521475847. The reversal of 521475840 is 48574125.

521475840 is a `hidden beast` number, since 521 + 47 + 58 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is a junction number, because it is equal to n+sod(n) for n = 521475795 and 521475804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521475847) 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, 2730145 + ... + 2730335.

It is an arithmetic number, because the mean of its divisors is an integer number (6540800).

Almost surely, 2^521475840 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 521475840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (941875200).

521475840 is an abundant number, since it is smaller than the sum of its proper divisors (1362274560).

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

521475840 is a wasteful number, since it uses less digits than its factorization.

521475840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 44800, while the sum is 36.

The square root of 521475840 is about 22835.8455065715. The cubic root of 521475840 is about 804.9051956818.

The spelling of 521475840 in words is "five hundred twenty-one million, four hundred seventy-five thousand, eight hundred forty".