505655917 has 4 divisors (see below), whose sum is σ = 544552540. Its totient is φ = 466759296.

The previous prime is 505655869. The next prime is 505655921. The reversal of 505655917 is 719556505.

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

It can be written as a sum of positive squares in 2 ways, for example, as 71808676 + 433847241 = 8474^2 + 20829^2 .

It is a cyclic number.

It is not a de Polignac number, because 505655917 - 2²⁷ = 371438189 is a prime.

It is a super-2 number, since 2×505655917² = 511375812794221778, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505655317) 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, 19448292 + ... + 19448317.

It is an arithmetic number, because the mean of its divisors is an integer number (136138135).

Almost surely, 2^505655917 is an apocalyptic number.

It is an amenable number.

505655917 is a deficient number, since it is larger than the sum of its proper divisors (38896623).

505655917 is a wasteful number, since it uses less digits than its factorization.

505655917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38896622.

The product of its (nonzero) digits is 236250, while the sum is 43.

The square root of 505655917 is about 22486.7942801992. The cubic root of 505655917 is about 796.6820481227.

The spelling of 505655917 in words is "five hundred five million, six hundred fifty-five thousand, nine hundred seventeen".