517809139 has 4 divisors (see below), whose sum is σ = 529851256. Its totient is φ = 505767024.

The previous prime is 517809107. The next prime is 517809161. The reversal of 517809139 is 931908715.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 517809139 - 2⁵ = 517809107 is a prime.

It is a super-4 number, since 4×517809139⁴ (a number of 36 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 12042073 = 517809139 / (5 + 1 + 7 + 8 + 0 + 9 + 1 + 3 + 9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 517809095 and 517809104.

It is not an unprimeable number, because it can be changed into a prime (517809179) 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 in 3 ways as a sum of consecutive naturals, for example, 6020994 + ... + 6021079.

It is an arithmetic number, because the mean of its divisors is an integer number (132462814).

Almost surely, 2^517809139 is an apocalyptic number.

517809139 is a deficient number, since it is larger than the sum of its proper divisors (12042117).

517809139 is a wasteful number, since it uses less digits than its factorization.

517809139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12042116.

The product of its (nonzero) digits is 68040, while the sum is 43.

The square root of 517809139 is about 22755.4199917294. The cubic root of 517809139 is about 803.0142220475.

The spelling of 517809139 in words is "five hundred seventeen million, eight hundred nine thousand, one hundred thirty-nine".