16561560016 has 40 divisors (see below), whose sum is σ = 32564824200. Its totient is φ = 8158402560.

The previous prime is 16561559981. The next prime is 16561560017. The reversal of 16561560016 is 61006516561.

It can be written as a sum of positive squares in 4 ways, for example, as 2756250000 + 13805310016 = 52500^2 + 117496^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16561560017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 379450 + ... + 420838.

It is an arithmetic number, because the mean of its divisors is an integer number (814120605).

Almost surely, 2^16561560016 is an apocalyptic number.

16561560016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

16561560016 is a deficient number, since it is larger than the sum of its proper divisors (16003264184).

16561560016 is a wasteful number, since it uses less digits than its factorization.

16561560016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41767 (or 41761 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 37.

The spelling of 16561560016 in words is "sixteen billion, five hundred sixty-one million, five hundred sixty thousand, sixteen".