520421 has 16 divisors (see below), whose sum is σ = 632448. Its totient is φ = 425920.

The previous prime is 520411. The next prime is 520423. The reversal of 520421 is 124025.

It is not a de Polignac number, because 520421 - 2⁶ = 520357 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 520396 and 520405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22616 + ... + 22638.

It is an arithmetic number, because the mean of its divisors is an integer number (39528).

2⁵²⁰⁴²¹ is an apocalyptic number.

It is an amenable number.

520421 is a deficient number, since it is larger than the sum of its proper divisors (112027).

520421 is a wasteful number, since it uses less digits than its factorization.

520421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 520421 is about 721.4021070111. The cubic root of 520421 is about 80.4362109273.

Adding to 520421 its reverse (124025), we get a palindrome (644446).

It can be divided in two parts, 5204 and 21, that added together give a palindrome (5225).

The spelling of 520421 in words is "five hundred twenty thousand, four hundred twenty-one".