217214660 has 24 divisors (see below), whose sum is σ = 491239896. Its totient is φ = 80202240.

The previous prime is 217214653. The next prime is 217214663. The reversal of 217214660 is 66412712.

It can be written as a sum of positive squares in 4 ways, for example, as 28536964 + 188677696 = 5342^2 + 13736^2 .

It is not an unprimeable number, because it can be changed into a prime (217214663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417461 + ... + 417980.

It is an arithmetic number, because the mean of its divisors is an integer number (20468329).

Almost surely, 2^217214660 is an apocalyptic number.

217214660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217214660 is an abundant number, since it is smaller than the sum of its proper divisors (274025236).

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

217214660 is a wasteful number, since it uses less digits than its factorization.

217214660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835463 (or 835461 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 217214660 is about 14738.2040968362. The cubic root of 217214660 is about 601.1225835522.

The spelling of 217214660 in words is "two hundred seventeen million, two hundred fourteen thousand, six hundred sixty".