531993509 has 2 divisors, whose sum is σ = 531993510. Its totient is φ = 531993508.

The previous prime is 531993479. The next prime is 531993523. The reversal of 531993509 is 905399135.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 336832609 + 195160900 = 18353^2 + 13970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-531993509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 531993509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (531993599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265996754 + 265996755.

It is an arithmetic number, because the mean of its divisors is an integer number (265996755).

Almost surely, 2^531993509 is an apocalyptic number.

It is an amenable number.

531993509 is a deficient number, since it is larger than the sum of its proper divisors (1).

531993509 is an equidigital number, since it uses as much as digits as its factorization.

531993509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164025, while the sum is 44.

The square root of 531993509 is about 23064.9844786421. The cubic root of 531993509 is about 810.2806064318.

The spelling of 531993509 in words is "five hundred thirty-one million, nine hundred ninety-three thousand, five hundred nine".