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216720 = 24325743
BaseRepresentation
bin110100111010010000
3102000021200
4310322100
523413340
64351200
71561560
oct647220
9360250
10216720
11138909
12a5500
137784a
1458da0
1544330
hex34e90

216720 has 120 divisors (see below), whose sum is σ = 851136. Its totient is φ = 48384.

The previous prime is 216719. The next prime is 216731. The reversal of 216720 is 27612.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 12 and base 15.

It is a junction number, because it is equal to n+sod(n) for n = 216693 and 216702.

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, 5019 + ... + 5061.

2216720 is an apocalyptic number.

216720 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 216720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (425568).

216720 is an abundant number, since it is smaller than the sum of its proper divisors (634416).

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

216720 is a wasteful number, since it uses less digits than its factorization.

216720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 216720 is about 465.5319537905. The cubic root of 216720 is about 60.0665927295.

It can be divided in two parts, 2167 and 20, that added together give a 7-th power (2187 = 37).

The spelling of 216720 in words is "two hundred sixteen thousand, seven hundred twenty".