644547087068 has 12 divisors (see below), whose sum is σ = 1128974504280. Its totient is φ = 321982942992.

The previous prime is 644547087053. The next prime is 644547087103. The reversal of 644547087068 is 860780745446.

It is a junction number, because it is equal to n+sod(n) for n = 644547086998 and 644547087016.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 72645146 + ... + 72654017.

It is an arithmetic number, because the mean of its divisors is an integer number (94081208690).

Almost surely, 2^644547087068 is an apocalyptic number.

It is an amenable number.

644547087068 is a deficient number, since it is larger than the sum of its proper divisors (484427417212).

644547087068 is a wasteful number, since it uses less digits than its factorization.

644547087068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145300276 (or 145300274 counting only the distinct ones).

The product of its (nonzero) digits is 36126720, while the sum is 59.

The spelling of 644547087068 in words is "six hundred forty-four billion, five hundred forty-seven million, eighty-seven thousand, sixty-eight".