521055240 has 128 divisors (see below), whose sum is σ = 1656201600. Its totient is φ = 130775040.

The previous prime is 521055193. The next prime is 521055277. The reversal of 521055240 is 42550125.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 521055240.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 393780 + ... + 395100.

It is an arithmetic number, because the mean of its divisors is an integer number (12939075).

Almost surely, 2^521055240 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 521055240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (828100800).

521055240 is an abundant number, since it is smaller than the sum of its proper divisors (1135146360).

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

521055240 is a wasteful number, since it uses less digits than its factorization.

521055240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1527 (or 1523 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 521055240 is about 22826.6344431237. The cubic root of 521055240 is about 804.6887368303.

The spelling of 521055240 in words is "five hundred twenty-one million, fifty-five thousand, two hundred forty".