505147561 has 4 divisors (see below), whose sum is σ = 510149124. Its totient is φ = 500146000.

The previous prime is 505147553. The next prime is 505147603. The reversal of 505147561 is 165741505.

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 489781161 + 15366400 = 22131^2 + 3920^2 .

It is a cyclic number.

It is not a de Polignac number, because 505147561 - 2³ = 505147553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (505147541) 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, 2500630 + ... + 2500831.

It is an arithmetic number, because the mean of its divisors is an integer number (127537281).

Almost surely, 2^505147561 is an apocalyptic number.

It is an amenable number.

505147561 is a deficient number, since it is larger than the sum of its proper divisors (5001563).

505147561 is a wasteful number, since it uses less digits than its factorization.

505147561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5001562.

The product of its (nonzero) digits is 21000, while the sum is 34.

The square root of 505147561 is about 22475.4880036007. The cubic root of 505147561 is about 796.4149798906.

The spelling of 505147561 in words is "five hundred five million, one hundred forty-seven thousand, five hundred sixty-one".