656684449 has 8 divisors (see below), whose sum is σ = 697071528. Its totient is φ = 616492800.

The previous prime is 656684411. The next prime is 656684489. The reversal of 656684449 is 944486656.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 43230625 + 613453824 = 6575^2 + 24768^2 .

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 656684449 - 2¹³ = 656676257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 656684396 and 656684405.

It is not an unprimeable number, because it can be changed into a prime (656684489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41902 + ... + 55399.

It is an arithmetic number, because the mean of its divisors is an integer number (87133941).

Almost surely, 2^656684449 is an apocalyptic number.

It is an amenable number.

656684449 is a deficient number, since it is larger than the sum of its proper divisors (40387079).

656684449 is a wasteful number, since it uses less digits than its factorization.

656684449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97715.

The product of its digits is 4976640, while the sum is 52.

The square root of 656684449 is about 25625.8550881722. The cubic root of 656684449 is about 869.1983847991.

The spelling of 656684449 in words is "six hundred fifty-six million, six hundred eighty-four thousand, four hundred forty-nine".