216521895015072 has 144 divisors (see below), whose sum is σ = 622571236166880. Its totient is φ = 71375079246336.

The previous prime is 216521895015059. The next prime is 216521895015089. The reversal of 216521895015072 is 270510598125612.

It is a happy number.

216521895015072 is a `hidden beast` number, since 2 + 1 + 6 + 5 + 2 + 1 + 89 + 50 + 1 + 507 + 2 = 666.

216521895015072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×216521895015072² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9823983 + ... + 23012049.

It is an arithmetic number, because the mean of its divisors is an integer number (4323411362270).

Almost surely, 2^{216521895015072} 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 216521895015072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311285618083440).

216521895015072 is an abundant number, since it is smaller than the sum of its proper divisors (406049341151808).

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

216521895015072 is a wasteful number, since it uses less digits than its factorization.

216521895015072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13188715 (or 13188704 counting only the distinct ones).

The product of its (nonzero) digits is 3024000, while the sum is 54.

The spelling of 216521895015072 in words is "two hundred sixteen trillion, five hundred twenty-one billion, eight hundred ninety-five million, fifteen thousand, seventy-two".