217650340 has 12 divisors (see below), whose sum is σ = 457065756. Its totient is φ = 87060128.

The previous prime is 217650331. The next prime is 217650341. The reversal of 217650340 is 43056712.

It can be written as a sum of positive squares in 2 ways, for example, as 23270976 + 194379364 = 4824^2 + 13942^2 .

It is a junction number, because it is equal to n+sod(n) for n = 217650299 and 217650308.

It is not an unprimeable number, because it can be changed into a prime (217650341) 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 in 3 ways as a sum of consecutive naturals, for example, 5441239 + ... + 5441278.

It is an arithmetic number, because the mean of its divisors is an integer number (38088813).

Almost surely, 2^217650340 is an apocalyptic number.

217650340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217650340 is an abundant number, since it is smaller than the sum of its proper divisors (239415416).

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

217650340 is a wasteful number, since it uses less digits than its factorization.

217650340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10882526 (or 10882524 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 217650340 is about 14752.9773266280. The cubic root of 217650340 is about 601.5242172501.

The spelling of 217650340 in words is "two hundred seventeen million, six hundred fifty thousand, three hundred forty".