521531249 has 2 divisors, whose sum is σ = 521531250. Its totient is φ = 521531248.

The previous prime is 521531239. The next prime is 521531251. The reversal of 521531249 is 942135125.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 374151649 + 147379600 = 19343^2 + 12140^2 .

It is a cyclic number.

It is not a de Polignac number, because 521531249 - 2²⁰ = 520482673 is a prime.

Together with 521531251, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (521531239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260765624 + 260765625.

It is an arithmetic number, because the mean of its divisors is an integer number (260765625).

Almost surely, 2^521531249 is an apocalyptic number.

It is an amenable number.

521531249 is a deficient number, since it is larger than the sum of its proper divisors (1).

521531249 is an equidigital number, since it uses as much as digits as its factorization.

521531249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 32.

The square root of 521531249 is about 22837.0586766335. The cubic root of 521531249 is about 804.9337028590.

The spelling of 521531249 in words is "five hundred twenty-one million, five hundred thirty-one thousand, two hundred forty-nine".