525309 has 4 divisors (see below), whose sum is σ = 700416. Its totient is φ = 350204.

The previous prime is 525299. The next prime is 525313. The reversal of 525309 is 903525.

525309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 cyclic number.

It is not a de Polignac number, because 525309 - 2¹¹ = 523261 is a prime.

It is a D-number.

525309 is a lucky number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (525359) 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, 87549 + ... + 87554.

It is an arithmetic number, because the mean of its divisors is an integer number (175104).

2⁵²⁵³⁰⁹ is an apocalyptic number.

It is an amenable number.

525309 is a deficient number, since it is larger than the sum of its proper divisors (175107).

525309 is a wasteful number, since it uses less digits than its factorization.

525309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175106.

The product of its (nonzero) digits is 1350, while the sum is 24.

The square root of 525309 is about 724.7820362012. The cubic root of 525309 is about 80.6872561639.

The spelling of 525309 in words is "five hundred twenty-five thousand, three hundred nine".