511005661 has 8 divisors (see below), whose sum is σ = 513849600. Its totient is φ = 508168080.

The previous prime is 511005653. The next prime is 511005683. The reversal of 511005661 is 166500115.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 511005661 - 2³ = 511005653 is a prime.

It is a super-3 number, since 3×511005661³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (511005611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 314431 + ... + 316051.

It is an arithmetic number, because the mean of its divisors is an integer number (64231200).

Almost surely, 2^511005661 is an apocalyptic number.

It is an amenable number.

511005661 is a deficient number, since it is larger than the sum of its proper divisors (2843939).

511005661 is a wasteful number, since it uses less digits than its factorization.

511005661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3179.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 511005661 is about 22605.4343245159. The cubic root of 511005661 is about 799.4817794860.

Adding to 511005661 its reverse (166500115), we get a palindrome (677505776).

The spelling of 511005661 in words is "five hundred eleven million, five thousand, six hundred sixty-one".