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BaseRepresentation
bin10010101000110000…
…101101100100001101
31220122121121211212202
4102220300231210031
5311440332223041
613105405411245
71305616326044
oct225060554415
956577554782
1020011211021
11853989702a
123a65869b25
131b6bb01789
14d7b9a355b
157c1c32a9b
hex4a8c2d90d

20011211021 has 2 divisors, whose sum is σ = 20011211022. Its totient is φ = 20011211020.

The previous prime is 20011210993. The next prime is 20011211023. The reversal of 20011211021 is 12011211002.

Adding to 20011211021 its reverse (12011211002), we get a palindrome (32022422023).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19317942121 + 693268900 = 138989^2 + 26330^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011211021 - 210 = 20011209997 is a prime.

Together with 20011211023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20011210993 and 20011211011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20011211023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005605510 + 10005605511.

It is an arithmetic number, because the mean of its divisors is an integer number (10005605511).

Almost surely, 220011211021 is an apocalyptic number.

It is an amenable number.

20011211021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011211021 is an equidigital number, since it uses as much as digits as its factorization.

20011211021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 11.

The spelling of 20011211021 in words is "twenty billion, eleven million, two hundred eleven thousand, twenty-one".