16781055616 has 64 divisors (see below), whose sum is σ = 36509961600. Its totient is φ = 7635962880.

The previous prime is 16781055547. The next prime is 16781055647. The reversal of 16781055616 is 61655018761.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47125 + ... + 189163.

It is an arithmetic number, because the mean of its divisors is an integer number (570468150).

Almost surely, 2^16781055616 is an apocalyptic number.

16781055616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16781055616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18254980800).

16781055616 is an abundant number, since it is smaller than the sum of its proper divisors (19728905984).

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

16781055616 is a wasteful number, since it uses less digits than its factorization.

16781055616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142137 (or 142125 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 46.

The spelling of 16781055616 in words is "sixteen billion, seven hundred eighty-one million, fifty-five thousand, six hundred sixteen".