660500661 has 4 divisors (see below), whose sum is σ = 880667552. Its totient is φ = 440333772.

The previous prime is 660500623. The next prime is 660500669. The reversal of 660500661 is 166005066.

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 not a de Polignac number, because 660500661 - 2¹⁸ = 660238517 is a prime.

It is a super-2 number, since 2×660500661² = 872522246362873842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660500669) 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, 110083441 + ... + 110083446.

It is an arithmetic number, because the mean of its divisors is an integer number (220166888).

Almost surely, 2^660500661 is an apocalyptic number.

It is an amenable number.

660500661 is a deficient number, since it is larger than the sum of its proper divisors (220166891).

660500661 is a wasteful number, since it uses less digits than its factorization.

660500661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220166890.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 660500661 is about 25700.2074116144. The cubic root of 660500661 is about 870.8788674577.

The spelling of 660500661 in words is "six hundred sixty million, five hundred thousand, six hundred sixty-one".