506991361 has 4 divisors (see below), whose sum is σ = 507103300. Its totient is φ = 506879424.

The previous prime is 506991349. The next prime is 506991367. The reversal of 506991361 is 163199605.

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 3841600 + 503149761 = 1960^2 + 22431^2 .

It is a cyclic number.

It is not a de Polignac number, because 506991361 - 2²¹ = 504894209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (506991367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48876 + ... + 58333.

It is an arithmetic number, because the mean of its divisors is an integer number (126775825).

Almost surely, 2^506991361 is an apocalyptic number.

It is an amenable number.

506991361 is a deficient number, since it is larger than the sum of its proper divisors (111939).

506991361 is a wasteful number, since it uses less digits than its factorization.

506991361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111938.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 506991361 is about 22516.4686618484. The cubic root of 506991361 is about 797.3827808966.

The spelling of 506991361 in words is "five hundred six million, nine hundred ninety-one thousand, three hundred sixty-one".