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21020000 = 25541051
BaseRepresentation
bin101000000101…
…1110101100000
31110112221000112
41100023311200
520340120000
62030310452
7343444541
oct120136540
943487015
1021020000
1110957701
127058428
13447c791
142b124c8
151ca3235
hex140bd60

21020000 has 60 divisors (see below), whose sum is σ = 51761556. Its totient is φ = 8400000.

The previous prime is 21019993. The next prime is 21020011. The reversal of 21020000 is 2012.

Adding to 21020000 its reverse (2012), we get a palindrome (21022012).

It is a Harshad number since it is a multiple of its sum of digits (5).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 19475 + ... + 20525.

Almost surely, 221020000 is an apocalyptic number.

21020000 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 21020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25880778).

21020000 is an abundant number, since it is smaller than the sum of its proper divisors (30741556).

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

21020000 is an equidigital number, since it uses as much as digits as its factorization.

21020000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081 (or 1058 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 5.

The square root of 21020000 is about 4584.7573545391. The cubic root of 21020000 is about 275.9799747426.

The spelling of 21020000 in words is "twenty-one million, twenty thousand".

Divisors: 1 2 4 5 8 10 16 20 25 32 40 50 80 100 125 160 200 250 400 500 625 800 1000 1051 1250 2000 2102 2500 4000 4204 5000 5255 8408 10000 10510 16816 20000 21020 26275 33632 42040 52550 84080 105100 131375 168160 210200 262750 420400 525500 656875 840800 1051000 1313750 2102000 2627500 4204000 5255000 10510000 21020000