521920 has 56 divisors (see below), whose sum is σ = 1426464. Its totient is φ = 178176.

The previous prime is 521903. The next prime is 521923. The reversal of 521920 is 29125.

It is a tau number, because it is divible by the number of its divisors (56).

It is not an unprimeable number, because it can be changed into a prime (521923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2124 + ... + 2356.

2⁵²¹⁹²⁰ 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 521920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (713232).

521920 is an abundant number, since it is smaller than the sum of its proper divisors (904544).

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

521920 is a wasteful number, since it uses less digits than its factorization.

521920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 247 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 521920 is about 722.4403089529. The cubic root of 521920 is about 80.5133653207.

It can be divided in two parts, 521 and 920, that added together give a palindrome (1441).

The spelling of 521920 in words is "five hundred twenty-one thousand, nine hundred twenty".