520171685 has 16 divisors (see below), whose sum is σ = 682117632. Its totient is φ = 377659200.

The previous prime is 520171681. The next prime is 520171693. The reversal of 520171685 is 586171025.

It is not a de Polignac number, because 520171685 - 2² = 520171681 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (520171681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25595 + ... + 41175.

It is an arithmetic number, because the mean of its divisors is an integer number (42632352).

Almost surely, 2^520171685 is an apocalyptic number.

520171685 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

520171685 is a deficient number, since it is larger than the sum of its proper divisors (161945947).

520171685 is a wasteful number, since it uses less digits than its factorization.

520171685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16204.

The product of its (nonzero) digits is 16800, while the sum is 35.

The square root of 520171685 is about 22807.2726339648. The cubic root of 520171685 is about 804.2336417621.

The spelling of 520171685 in words is "five hundred twenty million, one hundred seventy-one thousand, six hundred eighty-five".