648759640068 has 18 divisors (see below), whose sum is σ = 1639920201374. Its totient is φ = 216253213344.

The previous prime is 648759640057. The next prime is 648759640069. The reversal of 648759640068 is 860046957846.

648759640068 is a `hidden beast` number, since 6 + 4 + 87 + 5 + 96 + 400 + 68 = 666.

It can be written as a sum of positive squares in only one way, i.e., 480149213184 + 168610426884 = 692928^2 + 410622^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×648759640068² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 648759639987 and 648759640014.

It is not an unprimeable number, because it can be changed into a prime (648759640069) 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 5 ways as a sum of consecutive naturals, for example, 9010550521 + ... + 9010550592.

Almost surely, 2^648759640068 is an apocalyptic number.

It is an amenable number.

648759640068 is an abundant number, since it is smaller than the sum of its proper divisors (991160561306).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

648759640068 is a wasteful number, since it uses less digits than its factorization.

648759640068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18021101123 (or 18021101118 counting only the distinct ones).

The product of its (nonzero) digits is 69672960, while the sum is 63.

The spelling of 648759640068 in words is "six hundred forty-eight billion, seven hundred fifty-nine million, six hundred forty thousand, sixty-eight".