216709240 has 64 divisors (see below), whose sum is σ = 537010560. Its totient is φ = 78049920.

The previous prime is 216709223. The next prime is 216709267. The reversal of 216709240 is 42907612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44779 + ... + 49381.

It is an arithmetic number, because the mean of its divisors is an integer number (8390790).

Almost surely, 2^216709240 is an apocalyptic number.

216709240 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 216709240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268505280).

216709240 is an abundant number, since it is smaller than the sum of its proper divisors (320301320).

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

216709240 is a wasteful number, since it uses less digits than its factorization.

216709240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4732 (or 4728 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 216709240 is about 14721.0475170757. The cubic root of 216709240 is about 600.6559862457.

The spelling of 216709240 in words is "two hundred sixteen million, seven hundred nine thousand, two hundred forty".