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21488980 = 2255918211
BaseRepresentation
bin101000111111…
…0010101010100
31111102202100011
41101332111110
521000121410
62044330004
7350440042
oct121762524
944382304
1021488980
1111147a97
127243904
1345b5096
142bd5392
151d4718a
hex147e554

21488980 has 24 divisors (see below), whose sum is σ = 45894240. Its totient is φ = 8449440.

The previous prime is 21488963. The next prime is 21489001. The reversal of 21488980 is 8988412.

It is a super-2 number, since 2×214889802 = 923552522880800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7926 + ... + 10285.

It is an arithmetic number, because the mean of its divisors is an integer number (1912260).

Almost surely, 221488980 is an apocalyptic number.

21488980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21488980 is an abundant number, since it is smaller than the sum of its proper divisors (24405260).

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

21488980 is a wasteful number, since it uses less digits than its factorization.

21488980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18279 (or 18277 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 21488980 is about 4635.6207782777. The cubic root of 21488980 is about 278.0173720662.

The spelling of 21488980 in words is "twenty-one million, four hundred eighty-eight thousand, nine hundred eighty".

Divisors: 1 2 4 5 10 20 59 118 236 295 590 1180 18211 36422 72844 91055 182110 364220 1074449 2148898 4297796 5372245 10744490 21488980