509746 has 4 divisors (see below), whose sum is σ = 764622. Its totient is φ = 254872.

The previous prime is 509741. The next prime is 509767. The reversal of 509746 is 647905.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 647905 = 5 ⋅129581.

It can be written as a sum of positive squares in only one way, i.e., 505521 + 4225 = 711^2 + 65^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (509741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127435 + ... + 127438.

2⁵⁰⁹⁷⁴⁶ is an apocalyptic number.

509746 is a deficient number, since it is larger than the sum of its proper divisors (254876).

509746 is a wasteful number, since it uses less digits than its factorization.

509746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254875.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 509746 is about 713.9649851358. The cubic root of 509746 is about 79.8824314718.

The spelling of 509746 in words is "five hundred nine thousand, seven hundred forty-six".