521630340 has 192 divisors, whose sum is σ = 1900523520. Its totient is φ = 103656960.

The previous prime is 521630339. The next prime is 521630353. The reversal of 521630340 is 43036125.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 521630340.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 103806 + ... + 108714.

It is an arithmetic number, because the mean of its divisors is an integer number (9898560).

Almost surely, 2^521630340 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 521630340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (950261760).

521630340 is an abundant number, since it is smaller than the sum of its proper divisors (1378893180).

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

521630340 is a wasteful number, since it uses less digits than its factorization.

521630340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4962 (or 4960 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 521630340 is about 22839.2280955377. The cubic root of 521630340 is about 804.9846787974.

Adding to 521630340 its reverse (43036125), we get a palindrome (564666465).

The spelling of 521630340 in words is "five hundred twenty-one million, six hundred thirty thousand, three hundred forty".