218886429609 has 27 divisors (see below), whose sum is σ = 317879428503. Its totient is φ = 145139229072.

The previous prime is 218886429571. The next prime is 218886429623. The reversal of 218886429609 is 906924688812.

The square root of 218886429609 is 467853.

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

218886429609 is a `hidden beast` number, since 2 + 18 + 8 + 8 + 6 + 4 + 2 + 9 + 609 = 666.

It can be written as a sum of positive squares in only one way, i.e., 37727235225 + 181159194384 = 194235^2 + 425628^2 .

It is not a de Polignac number, because 218886429609 - 2⁷ = 218886429481 is a prime.

It is a super-2 number, since 2×218886429609² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (218886429649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 388785562 + ... + 388786124.

Almost surely, 2^218886429609 is an apocalyptic number.

218886429609 is the 467853-rd square number.

218886429609 is the 233927-th centered octagonal number.

It is an amenable number.

218886429609 is a deficient number, since it is larger than the sum of its proper divisors (98992998894).

218886429609 is an frugal number, since it uses more digits than its factorization.

218886429609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1686 (or 843 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 63.

The spelling of 218886429609 in words is "two hundred eighteen billion, eight hundred eighty-six million, four hundred twenty-nine thousand, six hundred nine".