642068066864 has 60 divisors (see below), whose sum is σ = 1447411884264. Its totient is φ = 275114633472.

The previous prime is 642068066819. The next prime is 642068066867. The reversal of 642068066864 is 468660860246.

642068066864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is not an unprimeable number, because it can be changed into a prime (642068066867) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3787667 + ... + 3953549.

Almost surely, 2^642068066864 is an apocalyptic number.

It is an amenable number.

642068066864 is an abundant number, since it is smaller than the sum of its proper divisors (805343817400).

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

642068066864 is a wasteful number, since it uses less digits than its factorization.

642068066864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170842 (or 170829 counting only the distinct ones).

The product of its (nonzero) digits is 15925248, while the sum is 56.

The spelling of 642068066864 in words is "six hundred forty-two billion, sixty-eight million, sixty-six thousand, eight hundred sixty-four".