649108869680 has 80 divisors (see below), whose sum is σ = 1589643851520. Its totient is φ = 245817794304.

The previous prime is 649108869677. The next prime is 649108869719. The reversal of 649108869680 is 86968801946.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2206979 + ... + 2483741.

It is an arithmetic number, because the mean of its divisors is an integer number (19870548144).

Almost surely, 2^649108869680 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649108869680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (794821925760).

649108869680 is an abundant number, since it is smaller than the sum of its proper divisors (940534981840).

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

649108869680 is a wasteful number, since it uses less digits than its factorization.

649108869680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278338 (or 278332 counting only the distinct ones).

The product of its (nonzero) digits is 35831808, while the sum is 65.

The spelling of 649108869680 in words is "six hundred forty-nine billion, one hundred eight million, eight hundred sixty-nine thousand, six hundred eighty".