25563656617 has 8 divisors (see below), whose sum is σ = 25669158912. Its totient is φ = 25458201600.

The previous prime is 25563656597. The next prime is 25563656639. The reversal of 25563656617 is 71665636552.

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 25563656617 - 2¹⁵ = 25563623849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25563656317) 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, 1427992 + ... + 1445782.

It is an arithmetic number, because the mean of its divisors is an integer number (3208644864).

Almost surely, 2^25563656617 is an apocalyptic number.

It is an amenable number.

25563656617 is a deficient number, since it is larger than the sum of its proper divisors (105502295).

25563656617 is a wasteful number, since it uses less digits than its factorization.

25563656617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23639.

The product of its digits is 6804000, while the sum is 52.

The spelling of 25563656617 in words is "twenty-five billion, five hundred sixty-three million, six hundred fifty-six thousand, six hundred seventeen".