521390 has 16 divisors (see below), whose sum is σ = 994032. Its totient is φ = 196224.

The previous prime is 521377. The next prime is 521393. The reversal of 521390 is 93125.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1364 + ... + 1703.

It is an arithmetic number, because the mean of its divisors is an integer number (62127).

2⁵²¹³⁹⁰ is an apocalyptic number.

521390 is a deficient number, since it is larger than the sum of its proper divisors (472642).

521390 is a wasteful number, since it uses less digits than its factorization.

521390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3091.

The product of its (nonzero) digits is 270, while the sum is 20.

The square root of 521390 is about 722.0734034709. The cubic root of 521390 is about 80.4861028181.

The spelling of 521390 in words is "five hundred twenty-one thousand, three hundred ninety".