217313486981 has 8 divisors (see below), whose sum is σ = 230100704064. Its totient is φ = 204526722240.

The previous prime is 217313486977. The next prime is 217313487029. The reversal of 217313486981 is 189684313712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 217313486981 - 2² = 217313486977 is a prime.

It is a super-2 number, since 2×217313486981² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217313486381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1834166 + ... + 1949048.

It is an arithmetic number, because the mean of its divisors is an integer number (28762588008).

Almost surely, 2^217313486981 is an apocalyptic number.

It is an amenable number.

217313486981 is a deficient number, since it is larger than the sum of its proper divisors (12787217083).

217313486981 is a wasteful number, since it uses less digits than its factorization.

217313486981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226171.

The product of its digits is 1741824, while the sum is 53.

The spelling of 217313486981 in words is "two hundred seventeen billion, three hundred thirteen million, four hundred eighty-six thousand, nine hundred eighty-one".