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BaseRepresentation
bin111100000111100
31120020000
413200330
51441110
6354300
7155511
oct74074
946200
1030780
1121142
1215990
1311019
14b308
1591c0
hex783c

30780 has 60 divisors (see below), whose sum is σ = 101640. Its totient is φ = 7776.

The previous prime is 30773. The next prime is 30781. The reversal of 30780 is 8703.

It is a tau number, because it is divible by the number of its divisors (60).

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

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30781) by changing a digit.

30780 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1611 + ... + 1629.

It is an arithmetic number, because the mean of its divisors is an integer number (1694).

230780 is an apocalyptic number.

30780 is a gapful number since it is divisible by the number (30) 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 30780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50820).

30780 is an abundant number, since it is smaller than the sum of its proper divisors (70860).

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

30780 is a wasteful number, since it uses less digits than its factorization.

30780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40 (or 29 counting only the distinct ones).

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

The square root of 30780 is about 175.4422982066. The cubic root of 30780 is about 31.3393178047.

The spelling of 30780 in words is "thirty thousand, seven hundred eighty".