656530891 has 8 divisors (see below), whose sum is σ = 658875168. Its totient is φ = 654192000.

The previous prime is 656530879. The next prime is 656530907. The reversal of 656530891 is 198035656.

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 656530891 - 2⁹ = 656530379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656570891) 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 7 ways as a sum of consecutive naturals, for example, 555321 + ... + 556501.

It is an arithmetic number, because the mean of its divisors is an integer number (82359396).

Almost surely, 2^656530891 is an apocalyptic number.

656530891 is a deficient number, since it is larger than the sum of its proper divisors (2344277).

656530891 is a wasteful number, since it uses less digits than its factorization.

656530891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2693.

The product of its (nonzero) digits is 194400, while the sum is 43.

The square root of 656530891 is about 25622.8587593188. The cubic root of 656530891 is about 869.1306288823.

The spelling of 656530891 in words is "six hundred fifty-six million, five hundred thirty thousand, eight hundred ninety-one".