221608868258 has 6 divisors (see below), whose sum is σ = 332414301009. Its totient is φ = 110804101256.

The previous prime is 221608868231. The next prime is 221608868269. The reversal of 221608868258 is 852868806122.

It can be written as a sum of positive squares in 2 ways, for example, as 131868480769 + 89740387489 = 363137^2 + 299567^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=332873.

It is a super-2 number, since 2×221608868258² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 499310 + ... + 832182.

Almost surely, 2^221608868258 is an apocalyptic number.

221608868258 is a deficient number, since it is larger than the sum of its proper divisors (110805432751).

221608868258 is an frugal number, since it uses more digits than its factorization.

221608868258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665748 (or 332875 counting only the distinct ones).

The product of its (nonzero) digits is 5898240, while the sum is 56.

The spelling of 221608868258 in words is "two hundred twenty-one billion, six hundred eight million, eight hundred sixty-eight thousand, two hundred fifty-eight".