521423 has 4 divisors (see below), whose sum is σ = 595920. Its totient is φ = 446928.

The previous prime is 521401. The next prime is 521429. The reversal of 521423 is 324125.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 521423 - 2⁶ = 521359 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 (521429) 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, 37238 + ... + 37251.

It is an arithmetic number, because the mean of its divisors is an integer number (148980).

2⁵²¹⁴²³ is an apocalyptic number.

521423 is a deficient number, since it is larger than the sum of its proper divisors (74497).

521423 is an equidigital number, since it uses as much as digits as its factorization.

521423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74496.

The product of its digits is 240, while the sum is 17.

The square root of 521423 is about 722.0962539717. The cubic root of 521423 is about 80.4878008339.

Adding to 521423 its reverse (324125), we get a palindrome (845548).

The spelling of 521423 in words is "five hundred twenty-one thousand, four hundred twenty-three".