217040 has 20 divisors (see below), whose sum is σ = 504804. Its totient is φ = 86784.

The previous prime is 217033. The next prime is 217057. The reversal of 217040 is 40712.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 163216 + 53824 = 404^2 + 232^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1277 + ... + 1436.

2²¹⁷⁰⁴⁰ is an apocalyptic number.

217040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217040 is an abundant number, since it is smaller than the sum of its proper divisors (287764).

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

217040 is a wasteful number, since it uses less digits than its factorization.

217040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2726 (or 2720 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 217040 is about 465.8755198548. The cubic root of 217040 is about 60.0961421588.

Adding to 217040 its reverse (40712), we get a palindrome (257752).

The spelling of 217040 in words is "two hundred seventeen thousand, forty", and thus it is an iban number.