661600631546656 has 48 divisors (see below), whose sum is σ = 1311513958755000. Its totient is φ = 328518554165248.

The previous prime is 661600631546653. The next prime is 661600631546669. The reversal of 661600631546656 is 656645136006166.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 660721320250000 + 879311296656 = 25704500^2 + 937716^2 .

It is a junction number, because it is equal to n+sod(n) for n = 661600631546594 and 661600631546603.

It is not an unprimeable number, because it can be changed into a prime (661600631546653) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12418320 + ... + 38437168.

Almost surely, 2^{661600631546656} is an apocalyptic number.

It is an amenable number.

661600631546656 is a deficient number, since it is larger than the sum of its proper divisors (649913327208344).

661600631546656 is a wasteful number, since it uses less digits than its factorization.

661600631546656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26024341 (or 26024333 counting only the distinct ones).

The product of its (nonzero) digits is 83980800, while the sum is 61.

The spelling of 661600631546656 in words is "six hundred sixty-one trillion, six hundred billion, six hundred thirty-one million, five hundred forty-six thousand, six hundred fifty-six".