216218879410689 has 81 divisors (see below), whose sum is σ = 329845471568067. Its totient is φ = 136474084229472.

The previous prime is 216218879410679. The next prime is 216218879410691. The reversal of 216218879410689 is 986014978812612.

The square root of 216218879410689 is 14704383.

It is a perfect power (a square), and thus also a powerful number.

216218879410689 is a `hidden beast` number, since 2 + 1 + 6 + 2 + 1 + 88 + 79 + 410 + 68 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 33879768520689 + 182339110890000 = 5820633^2 + 13503300^2 .

It is not a de Polignac number, because 216218879410689 - 2¹³ = 216218879402497 is a prime.

It is a super-2 number, since 2×216218879410689² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216218879410679) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 104504048947 + ... + 104504051015.

Almost surely, 2^{216218879410689} is an apocalyptic number.

216218879410689 is the 14704383-rd square number.

216218879410689 is the 7352192-nd centered octagonal number.

It is an amenable number.

216218879410689 is a deficient number, since it is larger than the sum of its proper divisors (113626592157378).

216218879410689 is an frugal number, since it uses more digits than its factorization.

216218879410689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4396 (or 2198 counting only the distinct ones).

The product of its (nonzero) digits is 167215104, while the sum is 72.

The spelling of 216218879410689 in words is "two hundred sixteen trillion, two hundred eighteen billion, eight hundred seventy-nine million, four hundred ten thousand, six hundred eighty-nine".