521444440 has 64 divisors (see below), whose sum is σ = 1282275360. Its totient is φ = 189265920.

The previous prime is 521444387. The next prime is 521444479. The reversal of 521444440 is 44444125.

It is a junction number, because it is equal to n+sod(n) for n = 521444399 and 521444408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 429274 + ... + 430486.

Almost surely, 2^521444440 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 521444440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (641137680).

521444440 is an abundant number, since it is smaller than the sum of its proper divisors (760830920).

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

521444440 is a wasteful number, since it uses less digits than its factorization.

521444440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2212 (or 2208 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 28.

The square root of 521444440 is about 22835.1579806228. The cubic root of 521444440 is about 804.8890399123.

Adding to 521444440 its reverse (44444125), we get a palindrome (565888565).

The spelling of 521444440 in words is "five hundred twenty-one million, four hundred forty-four thousand, four hundred forty".