521491 has 2 divisors, whose sum is σ = 521492. Its totient is φ = 521490.

The previous prime is 521483. The next prime is 521497. The reversal of 521491 is 194125.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 521491 - 2³ = 521483 is a prime.

It is a zygodrome in base 3.

It is not a weakly prime, because it can be changed into another prime (521497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260745 + 260746.

It is an arithmetic number, because the mean of its divisors is an integer number (260746).

2⁵²¹⁴⁹¹ is an apocalyptic number.

521491 is a deficient number, since it is larger than the sum of its proper divisors (1).

521491 is an equidigital number, since it uses as much as digits as its factorization.

521491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 360, while the sum is 22.

The square root of 521491 is about 722.1433375723. The cubic root of 521491 is about 80.4912995496.

It can be divided in two parts, 5214 and 91, that multiplied together give a palindrome (474474).

The spelling of 521491 in words is "five hundred twenty-one thousand, four hundred ninety-one".