509798 has 4 divisors (see below), whose sum is σ = 764700. Its totient is φ = 254898.

The previous prime is 509797. The next prime is 509801. The reversal of 509798 is 897905.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 897905 = 5 ⋅179581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127448 + ... + 127451.

It is an arithmetic number, because the mean of its divisors is an integer number (191175).

2⁵⁰⁹⁷⁹⁸ is an apocalyptic number.

509798 is a deficient number, since it is larger than the sum of its proper divisors (254902).

509798 is a wasteful number, since it uses less digits than its factorization.

509798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254901.

The product of its (nonzero) digits is 22680, while the sum is 38.

The square root of 509798 is about 714.0014005589. The cubic root of 509798 is about 79.8851476907.

The spelling of 509798 in words is "five hundred nine thousand, seven hundred ninety-eight".