521243 has 2 divisors, whose sum is σ = 521244. Its totient is φ = 521242.

The previous prime is 521231. The next prime is 521251. The reversal of 521243 is 342125.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 521243 - 2⁶ = 521179 is a prime.

It is a Sophie Germain prime.

It is equal to p₄₃₁₅₄ and since 521243 and 43154 have the same sum of digits, it is a Honaker prime.

It is a zygodrome in base 3.

It is not a weakly prime, because it can be changed into another prime (521743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260621 + 260622.

It is an arithmetic number, because the mean of its divisors is an integer number (260622).

2⁵²¹²⁴³ is an apocalyptic number.

521243 is a deficient number, since it is larger than the sum of its proper divisors (1).

521243 is an equidigital number, since it uses as much as digits as its factorization.

521243 is an evil number, because the sum of its binary digits is even.

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

The square root of 521243 is about 721.9716060899. The cubic root of 521243 is about 80.4785380590.

Adding to 521243 its reverse (342125), we get a palindrome (863368).

The spelling of 521243 in words is "five hundred twenty-one thousand, two hundred forty-three".