217707138 has 48 divisors (see below), whose sum is σ = 515582496. Its totient is φ = 65843520.

The previous prime is 217707137. The next prime is 217707211. The reversal of 217707138 is 831707712.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (217707137) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 169045 + ... + 170327.

It is an arithmetic number, because the mean of its divisors is an integer number (10741302).

Almost surely, 2^217707138 is an apocalyptic number.

217707138 is an abundant number, since it is smaller than the sum of its proper divisors (297875358).

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

217707138 is a wasteful number, since it uses less digits than its factorization.

217707138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2159 (or 2156 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 36.

The square root of 217707138 is about 14754.9021684320. The cubic root of 217707138 is about 601.5765372556.

The spelling of 217707138 in words is "two hundred seventeen million, seven hundred seven thousand, one hundred thirty-eight".