217290638881 has 8 divisors (see below), whose sum is σ = 221025536000. Its totient is φ = 213561314640.

The previous prime is 217290638869. The next prime is 217290638891. The reversal of 217290638881 is 188836092712.

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 217290638881 - 2⁵ = 217290638849 is a prime.

It is a super-2 number, since 2×217290638881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217290638801) 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, 1314531 + ... + 1470568.

It is an arithmetic number, because the mean of its divisors is an integer number (27628192000).

Almost surely, 2^217290638881 is an apocalyptic number.

It is an amenable number.

217290638881 is a deficient number, since it is larger than the sum of its proper divisors (3734897119).

217290638881 is a wasteful number, since it uses less digits than its factorization.

217290638881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2786439.

The product of its (nonzero) digits is 2322432, while the sum is 55.

The spelling of 217290638881 in words is "two hundred seventeen billion, two hundred ninety million, six hundred thirty-eight thousand, eight hundred eighty-one".