16661512056 has 128 divisors (see below), whose sum is σ = 48576153600. Its totient is φ = 4663526400.

The previous prime is 16661511983. The next prime is 16661512111. The reversal of 16661512056 is 65021516661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9250356 + ... + 9252156.

It is an arithmetic number, because the mean of its divisors is an integer number (379501200).

Almost surely, 2^16661512056 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 16661512056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24288076800).

16661512056 is an abundant number, since it is smaller than the sum of its proper divisors (31914641544).

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

16661512056 is a wasteful number, since it uses less digits than its factorization.

16661512056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2909 (or 2905 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 16661512056 in words is "sixteen billion, six hundred sixty-one million, five hundred twelve thousand, fifty-six".