520985 has 8 divisors (see below), whose sum is σ = 646920. Its totient is φ = 402304.

The previous prime is 520981. The next prime is 521009. The reversal of 520985 is 589025.

520985 = T₄₅₄ + T₄₅₅ + ... + T₄₅₈.

It can be written as a sum of positive squares in 4 ways, for example, as 29584 + 491401 = 172^2 + 701^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 520985 - 2² = 520981 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520981) 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, 1652 + ... + 1941.

It is an arithmetic number, because the mean of its divisors is an integer number (80865).

2⁵²⁰⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

520985 is a deficient number, since it is larger than the sum of its proper divisors (125935).

520985 is a wasteful number, since it uses less digits than its factorization.

520985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3627.

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 520985 is about 721.7929065875. The cubic root of 520985 is about 80.4652576955.

The spelling of 520985 in words is "five hundred twenty thousand, nine hundred eighty-five".