215666615016 has 128 divisors (see below), whose sum is σ = 614600784000. Its totient is φ = 70049401344.

The previous prime is 215666615009. The next prime is 215666615029. The reversal of 215666615016 is 610516666512.

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, 1226350 + ... + 1391138.

It is an arithmetic number, because the mean of its divisors is an integer number (4801568625).

Almost surely, 2^215666615016 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 215666615016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (307300392000).

215666615016 is an abundant number, since it is smaller than the sum of its proper divisors (398934168984).

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

215666615016 is a wasteful number, since it uses less digits than its factorization.

215666615016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164960 (or 164950 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 215666615016 in words is "two hundred fifteen billion, six hundred sixty-six million, six hundred fifteen thousand, sixteen".