216678240 has 144 divisors (see below), whose sum is σ = 766937808. Its totient is φ = 57770496.

The previous prime is 216678211. The next prime is 216678263. The reversal of 216678240 is 42876612.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 216678195 and 216678204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36094 + ... + 41666.

It is an arithmetic number, because the mean of its divisors is an integer number (5325957).

Almost surely, 2^216678240 is an apocalyptic number.

216678240 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 216678240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (383468904).

216678240 is an abundant number, since it is smaller than the sum of its proper divisors (550259568).

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

216678240 is an equidigital number, since it uses as much as digits as its factorization.

216678240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5603 (or 5583 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 216678240 is about 14719.9945652164. The cubic root of 216678240 is about 600.6273438376.

The spelling of 216678240 in words is "two hundred sixteen million, six hundred seventy-eight thousand, two hundred forty".