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30980 = 2251549
BaseRepresentation
bin111100100000100
31120111102
413210010
51442410
6355232
7156215
oct74404
946442
1030980
1121304
1215b18
1311141
14b40c
1592a5
hex7904

30980 has 12 divisors (see below), whose sum is σ = 65100. Its totient is φ = 12384.

The previous prime is 30977. The next prime is 30983. The reversal of 30980 is 8903.

It is an interprime number because it is at equal distance from previous prime (30977) and next prime (30983).

It can be written as a sum of positive squares in 2 ways, for example, as 10816 + 20164 = 104^2 + 142^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1549 = 30980 / (3 + 0 + 9 + 8 + 0).

It is not an unprimeable number, because it can be changed into a prime (30983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 755 + ... + 794.

It is an arithmetic number, because the mean of its divisors is an integer number (5425).

230980 is an apocalyptic number.

It is an amenable number.

30980 is an abundant number, since it is smaller than the sum of its proper divisors (34120).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32550).

30980 is a wasteful number, since it uses less digits than its factorization.

30980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1558 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 30980 is about 176.0113632695. The cubic root of 30980 is about 31.4070494132.

The spelling of 30980 in words is "thirty thousand, nine hundred eighty".

Divisors: 1 2 4 5 10 20 1549 3098 6196 7745 15490 30980