505857389 has 12 divisors (see below), whose sum is σ = 541154772. Its totient is φ = 471225600.

The previous prime is 505857371. The next prime is 505857397. The reversal of 505857389 is 983758505.

It can be written as a sum of positive squares in 6 ways, for example, as 405015625 + 100841764 = 20125^2 + 10042^2 .

It is not a de Polignac number, because 505857389 - 2²⁴ = 489080173 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505857589) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 171959 + ... + 174875.

It is an arithmetic number, because the mean of its divisors is an integer number (45096231).

Almost surely, 2^505857389 is an apocalyptic number.

It is an amenable number.

505857389 is a deficient number, since it is larger than the sum of its proper divisors (35297383).

505857389 is a wasteful number, since it uses less digits than its factorization.

505857389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3136 (or 3035 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 50.

The square root of 505857389 is about 22491.2736188950. The cubic root of 505857389 is about 796.7878432608.

The spelling of 505857389 in words is "five hundred five million, eight hundred fifty-seven thousand, three hundred eighty-nine".