520240221 has 12 divisors (see below), whose sum is σ = 751982140. Its totient is φ = 346584960.

The previous prime is 520240211. The next prime is 520240223. The reversal of 520240221 is 122042025.

It can be written as a sum of positive squares in 2 ways, for example, as 210656196 + 309584025 = 14514^2 + 17595^2 .

It is not a de Polignac number, because 520240221 - 2⁷ = 520240093 is a prime.

It is a super-2 number, since 2×520240221² = 541299775092257682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 520240194 and 520240203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520240223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6010 + ... + 32811.

Almost surely, 2^520240221 is an apocalyptic number.

It is an amenable number.

520240221 is a deficient number, since it is larger than the sum of its proper divisors (231741919).

520240221 is a wasteful number, since it uses less digits than its factorization.

520240221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40316 (or 40313 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 520240221 is about 22808.7750876718. The cubic root of 520240221 is about 804.2689612139.

Adding to 520240221 its reverse (122042025), we get a palindrome (642282246).

The spelling of 520240221 in words is "five hundred twenty million, two hundred forty thousand, two hundred twenty-one".