521023220 has 12 divisors (see below), whose sum is σ = 1094148804. Its totient is φ = 208409280.

The previous prime is 521023219. The next prime is 521023253. The reversal of 521023220 is 22320125.

It can be written as a sum of positive squares in 2 ways, for example, as 357285604 + 163737616 = 18902^2 + 12796^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13025561 + ... + 13025600.

It is an arithmetic number, because the mean of its divisors is an integer number (91179067).

Almost surely, 2^521023220 is an apocalyptic number.

It is an amenable number.

521023220 is an abundant number, since it is smaller than the sum of its proper divisors (573125584).

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

521023220 is a wasteful number, since it uses less digits than its factorization.

521023220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26051170 (or 26051168 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 521023220 is about 22825.9330586944. The cubic root of 521023220 is about 804.6722531902.

Adding to 521023220 its reverse (22320125), we get a palindrome (543343345).

The spelling of 521023220 in words is "five hundred twenty-one million, twenty-three thousand, two hundred twenty".