217113986 has 4 divisors (see below), whose sum is σ = 325670982. Its totient is φ = 108556992.

The previous prime is 217113979. The next prime is 217113989. The reversal of 217113986 is 689311712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 189750625 + 27363361 = 13775^2 + 5231^2 .

It is not an unprimeable number, because it can be changed into a prime (217113989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54278495 + ... + 54278498.

Almost surely, 2^217113986 is an apocalyptic number.

217113986 is a deficient number, since it is larger than the sum of its proper divisors (108556996).

217113986 is a wasteful number, since it uses less digits than its factorization.

217113986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108556995.

The product of its digits is 18144, while the sum is 38.

The square root of 217113986 is about 14734.7882916586. The cubic root of 217113986 is about 601.0297003695.

The spelling of 217113986 in words is "two hundred seventeen million, one hundred thirteen thousand, nine hundred eighty-six".