506661661 has 4 divisors (see below), whose sum is σ = 552721824. Its totient is φ = 460601500.

The previous prime is 506661653. The next prime is 506661677. The reversal of 506661661 is 166166605.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 506661661 - 2³ = 506661653 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 506661661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (506661691) 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, 23030065 + ... + 23030086.

It is an arithmetic number, because the mean of its divisors is an integer number (138180456).

Almost surely, 2^506661661 is an apocalyptic number.

It is an amenable number.

506661661 is a deficient number, since it is larger than the sum of its proper divisors (46060163).

506661661 is a wasteful number, since it uses less digits than its factorization.

506661661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46060162.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 506661661 is about 22509.1461632822. The cubic root of 506661661 is about 797.2098955632.

The spelling of 506661661 in words is "five hundred six million, six hundred sixty-one thousand, six hundred sixty-one".