65657215663 has 4 divisors (see below), whose sum is σ = 70707770728. Its totient is φ = 60606660600.

The previous prime is 65657215661. The next prime is 65657215667. The reversal of 65657215663 is 36651275656.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65657215663 - 2¹ = 65657215661 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65657215663.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65657215661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2525277513 + ... + 2525277538.

It is an arithmetic number, because the mean of its divisors is an integer number (17676942682).

Almost surely, 2^65657215663 is an apocalyptic number.

65657215663 is a deficient number, since it is larger than the sum of its proper divisors (5050555065).

65657215663 is a wasteful number, since it uses less digits than its factorization.

65657215663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5050555064.

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

The spelling of 65657215663 in words is "sixty-five billion, six hundred fifty-seven million, two hundred fifteen thousand, six hundred sixty-three".