531947509 has 2 divisors, whose sum is σ = 531947510. Its totient is φ = 531947508.

The previous prime is 531947467. The next prime is 531947627. The reversal of 531947509 is 905749135.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 391169284 + 140778225 = 19778^2 + 11865^2 .

It is a cyclic number.

It is not a de Polignac number, because 531947509 - 2²⁷ = 397729781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (531947209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265973754 + 265973755.

It is an arithmetic number, because the mean of its divisors is an integer number (265973755).

Almost surely, 2^531947509 is an apocalyptic number.

It is an amenable number.

531947509 is a deficient number, since it is larger than the sum of its proper divisors (1).

531947509 is an equidigital number, since it uses as much as digits as its factorization.

531947509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 170100, while the sum is 43.

The square root of 531947509 is about 23063.9872745369. The cubic root of 531947509 is about 810.2572515214.

The spelling of 531947509 in words is "five hundred thirty-one million, nine hundred forty-seven thousand, five hundred nine".