217868260 has 48 divisors (see below), whose sum is σ = 496283760. Its totient is φ = 80015360.

The previous prime is 217868227. The next prime is 217868263. The reversal of 217868260 is 62868712.

It can be written as a sum of positive squares in 8 ways, for example, as 6340324 + 211527936 = 2518^2 + 14544^2 .

It is not an unprimeable number, because it can be changed into a prime (217868263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6126 + ... + 21754.

It is an arithmetic number, because the mean of its divisors is an integer number (10339245).

Almost surely, 2^217868260 is an apocalyptic number.

217868260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217868260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (248141880).

217868260 is an abundant number, since it is smaller than the sum of its proper divisors (278415500).

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

217868260 is a wasteful number, since it uses less digits than its factorization.

217868260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15696 (or 15694 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 217868260 is about 14760.3611066938. The cubic root of 217868260 is about 601.7249067794.

The spelling of 217868260 in words is "two hundred seventeen million, eight hundred sixty-eight thousand, two hundred sixty".