506620661 has 4 divisors (see below), whose sum is σ = 517399872. Its totient is φ = 495841452.

The previous prime is 506620649. The next prime is 506620703. The reversal of 506620661 is 166026605.

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, and also an emirpimes, since its reverse is a distinct semiprime: 166026605 = 5 ⋅33205321.

It is a cyclic number.

It is not a de Polignac number, because 506620661 - 2²² = 502426357 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 (506620061) 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, 5389535 + ... + 5389628.

It is an arithmetic number, because the mean of its divisors is an integer number (129349968).

Almost surely, 2^506620661 is an apocalyptic number.

It is an amenable number.

506620661 is a deficient number, since it is larger than the sum of its proper divisors (10779211).

506620661 is a wasteful number, since it uses less digits than its factorization.

506620661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10779210.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 506620661 is about 22508.2354039583. The cubic root of 506620661 is about 797.1883910828.

The spelling of 506620661 in words is "five hundred six million, six hundred twenty thousand, six hundred sixty-one".