509010661 has 4 divisors (see below), whose sum is σ = 509056812. Its totient is φ = 508964512.

The previous prime is 509010659. The next prime is 509010679. The reversal of 509010661 is 166010905.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 166010905 = 5 ⋅33202181.

It can be written as a sum of positive squares in 2 ways, for example, as 417425761 + 91584900 = 20431^2 + 9570^2 .

It is a cyclic number.

It is not a de Polignac number, because 509010661 - 2¹ = 509010659 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 (509040661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4275 + ... + 32191.

It is an arithmetic number, because the mean of its divisors is an integer number (127264203).

Almost surely, 2^509010661 is an apocalyptic number.

It is an amenable number.

509010661 is a deficient number, since it is larger than the sum of its proper divisors (46151).

509010661 is a wasteful number, since it uses less digits than its factorization.

509010661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46150.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 509010661 is about 22561.2646143783. The cubic root of 509010661 is about 798.4400126307.

It can be divided in two parts, 5090 and 10661, that added together give a palindrome (15751).

The spelling of 509010661 in words is "five hundred nine million, ten thousand, six hundred sixty-one".