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21201100 = 2252415171
BaseRepresentation
bin101000011100…
…0000011001100
31110220010102221
41100320003030
520411413400
62034225124
7345130534
oct120700314
943803387
1021201100
1110a70778
1271251a4
13451403b
142b5c4c4
151cdbc1a
hex14380cc

21201100 has 36 divisors (see below), whose sum is σ = 47137608. Its totient is φ = 8272000.

The previous prime is 21201083. The next prime is 21201109. The reversal of 21201100 is 110212.

Adding to 21201100 its reverse (110212), we get a palindrome (21311312).

It is not an unprimeable number, because it can be changed into a prime (21201109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1515 + ... + 6685.

It is an arithmetic number, because the mean of its divisors is an integer number (1309378).

Almost surely, 221201100 is an apocalyptic number.

21201100 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 21201100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23568804).

21201100 is an abundant number, since it is smaller than the sum of its proper divisors (25936508).

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

21201100 is a wasteful number, since it uses less digits than its factorization.

21201100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5226 (or 5219 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 21201100 is about 4604.4652241058. The cubic root of 21201100 is about 276.7702874708.

The spelling of 21201100 in words is "twenty-one million, two hundred one thousand, one hundred".