520645 has 8 divisors (see below), whose sum is σ = 645120. Its totient is φ = 402960.

The previous prime is 520633. The next prime is 520649. The reversal of 520645 is 546025.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 520645 - 2¹¹ = 518597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520649) 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, 1525 + ... + 1834.

It is an arithmetic number, because the mean of its divisors is an integer number (80640).

2⁵²⁰⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

520645 is a deficient number, since it is larger than the sum of its proper divisors (124475).

520645 is a wasteful number, since it uses less digits than its factorization.

520645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3395.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 520645 is about 721.5573435286. The cubic root of 520645 is about 80.4477497435.

It can be divided in two parts, 5206 and 45, that multiplied together give a triangular number (234270 = T₆₈₄).

The spelling of 520645 in words is "five hundred twenty thousand, six hundred forty-five".