521231040 has 168 divisors, whose sum is σ = 1955919888. Its totient is φ = 126351360.

The previous prime is 521231027. The next prime is 521231041. The reversal of 521231040 is 40132125.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (521231041) 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, 23454 + ... + 39906.

Almost surely, 2^521231040 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 521231040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (977959944).

521231040 is an abundant number, since it is smaller than the sum of its proper divisors (1434688848).

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

521231040 is a wasteful number, since it uses less digits than its factorization.

521231040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16487 (or 16474 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 521231040 is about 22830.4848831557. The cubic root of 521231040 is about 804.7792252357.

Adding to 521231040 its reverse (40132125), we get a palindrome (561363165).

The spelling of 521231040 in words is "five hundred twenty-one million, two hundred thirty-one thousand, forty".