208521 has 8 divisors (see below), whose sum is σ = 308960. Its totient is φ = 138996.

The previous prime is 208519. The next prime is 208529. The reversal of 208521 is 125802.

208521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 208521 - 2¹ = 208519 is a prime.

It is a Duffinian number.

208521 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 208494 and 208503.

It is not an unprimeable number, because it can be changed into a prime (208529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3835 + ... + 3888.

It is an arithmetic number, because the mean of its divisors is an integer number (38620).

2²⁰⁸⁵²¹ is an apocalyptic number.

It is an amenable number.

208521 is a deficient number, since it is larger than the sum of its proper divisors (100439).

208521 is an equidigital number, since it uses as much as digits as its factorization.

208521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7732 (or 7726 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 208521 is about 456.6409968454. The cubic root of 208521 is about 59.2993500076.

It can be divided in two parts, 208 and 521, that added together give a 6-th power (729 = 3⁶).

The spelling of 208521 in words is "two hundred eight thousand, five hundred twenty-one".