521620 has 24 divisors (see below), whose sum is σ = 1195488. Its totient is φ = 189600.

The previous prime is 521603. The next prime is 521641. The reversal of 521620 is 26125.

It is a happy number.

521620 is nontrivially palindromic in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 521594 and 521603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 966 + ... + 1405.

It is an arithmetic number, because the mean of its divisors is an integer number (49812).

2⁵²¹⁶²⁰ is an apocalyptic number.

It is an amenable number.

521620 is an abundant number, since it is smaller than the sum of its proper divisors (673868).

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

521620 is a wasteful number, since it uses less digits than its factorization.

521620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2391 (or 2389 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 521620 is about 722.2326494974. The cubic root of 521620 is about 80.4979359835.

Adding to 521620 its reverse (26125), we get a palindrome (547745).

The spelling of 521620 in words is "five hundred twenty-one thousand, six hundred twenty".