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BaseRepresentation
bin10101100100
31220010
4111210
521010
610220
74011
oct2544
91803
101380
111045
12970
13822
14708
15620
hex564

1380 has 24 divisors (see below), whose sum is σ = 4032. Its totient is φ = 352.

The previous prime is 1373. The next prime is 1381. The reversal of 1380 is 831.

Added to its reverse (831) it gives a triangular number (2211 = T66).

1380 is an esthetic number in base 5, because in such base its adjacent digits differ by 1.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 12, base 13 and base 15.

It is not an unprimeable number, because it can be changed into a prime (1381) by changing a digit.

1380 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49 + ... + 71.

It is an arithmetic number, because the mean of its divisors is an integer number (168).

1380 is a gapful number since it is divisible by the number (10) 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 1380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2016).

1380 is an abundant number, since it is smaller than the sum of its proper divisors (2652).

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

1380 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 9 representation: 1380 = (1803)9.

1380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35 (or 33 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1380 is about 37.1483512420. The cubic root of 1380 is about 11.1333628152.

Adding to 1380 its reverse (831), we get a triangular number (2211 = T66).

The spelling of 1380 in words is "one thousand, three hundred eighty".