216688206869136 has 60 divisors (see below), whose sum is σ = 612677838104332. Its totient is φ = 71484769271808.

The previous prime is 216688206869111. The next prime is 216688206869137. The reversal of 216688206869136 is 631968602886612.

It can be written as a sum of positive squares in 2 ways, for example, as 111878852198400 + 104809354670736 = 10577280^2 + 10237644^2 .

It is a super-2 number, since 2×216688206869136² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (216688206869137) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7756579921 + ... + 7756607856.

Almost surely, 2^{216688206869136} is an apocalyptic number.

It is an amenable number.

216688206869136 is an abundant number, since it is smaller than the sum of its proper divisors (395989631235196).

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

216688206869136 is a wasteful number, since it uses less digits than its factorization.

216688206869136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15513187888 (or 15513187879 counting only the distinct ones).

The product of its (nonzero) digits is 429981696, while the sum is 72.

The spelling of 216688206869136 in words is "two hundred sixteen trillion, six hundred eighty-eight billion, two hundred six million, eight hundred sixty-nine thousand, one hundred thirty-six".