517761493 has 4 divisors (see below), whose sum is σ = 520754508. Its totient is φ = 514768480.

The previous prime is 517761467. The next prime is 517761509. The reversal of 517761493 is 394167715.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 394167715 = 5 ⋅78833543.

It can be written as a sum of positive squares in 2 ways, for example, as 301612689 + 216148804 = 17367^2 + 14702^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-517761493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (517761793) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1496248 + ... + 1496593.

It is an arithmetic number, because the mean of its divisors is an integer number (130188627).

Almost surely, 2^517761493 is an apocalyptic number.

It is an amenable number.

517761493 is a deficient number, since it is larger than the sum of its proper divisors (2993015).

517761493 is a wasteful number, since it uses less digits than its factorization.

517761493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2993014.

The product of its digits is 158760, while the sum is 43.

The square root of 517761493 is about 22754.3730522289. The cubic root of 517761493 is about 802.9895916150.

The spelling of 517761493 in words is "five hundred seventeen million, seven hundred sixty-one thousand, four hundred ninety-three".