516515661 has 12 divisors (see below), whose sum is σ = 756299388. Its totient is φ = 339626304.

The previous prime is 516515647. The next prime is 516515689. The reversal of 516515661 is 166515615.

It can be written as a sum of positive squares in 2 ways, for example, as 334670436 + 181845225 = 18294^2 + 13485^2 .

It is not a de Polignac number, because 516515661 - 2⁷ = 516515533 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (516515611) 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 11 ways as a sum of consecutive naturals, for example, 392430 + ... + 393743.

It is an arithmetic number, because the mean of its divisors is an integer number (63024949).

Almost surely, 2^516515661 is an apocalyptic number.

It is an amenable number.

516515661 is a deficient number, since it is larger than the sum of its proper divisors (239783727).

516515661 is a wasteful number, since it uses less digits than its factorization.

516515661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786252 (or 786249 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The square root of 516515661 is about 22726.9809037628. The cubic root of 516515661 is about 802.3450261200.

The spelling of 516515661 in words is "five hundred sixteen million, five hundred fifteen thousand, six hundred sixty-one".