217068138 has 144 divisors (see below), whose sum is σ = 599249664. Its totient is φ = 56367360.

The previous prime is 217068127. The next prime is 217068151. The reversal of 217068138 is 831860712.

It is an unprimeable number.

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 in 71 ways as a sum of consecutive naturals, for example, 464581 + ... + 465047.

It is an arithmetic number, because the mean of its divisors is an integer number (4161456).

Almost surely, 2^217068138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217068138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (299624832).

217068138 is an abundant number, since it is smaller than the sum of its proper divisors (382181526).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217068138 is a wasteful number, since it uses less digits than its factorization.

217068138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 527 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 217068138 is about 14733.2324355519. The cubic root of 217068138 is about 600.9873908741.

The spelling of 217068138 in words is "two hundred seventeen million, sixty-eight thousand, one hundred thirty-eight".