521617 has 4 divisors (see below), whose sum is σ = 544320. Its totient is φ = 498916.

The previous prime is 521603. The next prime is 521641. The reversal of 521617 is 716125.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-521617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11317 + ... + 11362.

It is an arithmetic number, because the mean of its divisors is an integer number (136080).

2⁵²¹⁶¹⁷ is an apocalyptic number.

It is an amenable number.

521617 is a deficient number, since it is larger than the sum of its proper divisors (22703).

521617 is a wasteful number, since it uses less digits than its factorization.

521617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22702.

The product of its digits is 420, while the sum is 22.

The square root of 521617 is about 722.2305726013. The cubic root of 521617 is about 80.4977816603.

The spelling of 521617 in words is "five hundred twenty-one thousand, six hundred seventeen".