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1202120021 is a prime number
BaseRepresentation
bin100011110100110…
…1110010101010101
310002210000000122202
41013221232111111
54430220320041
6315141334245
741534565044
oct10751562525
93083000582
101202120021
11567624623
12296707385
1316208742b
14b592255b
1570808a9b
hex47a6e555

1202120021 has 2 divisors, whose sum is σ = 1202120022. Its totient is φ = 1202120020.

The previous prime is 1202119999. The next prime is 1202120027. The reversal of 1202120021 is 1200212021.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 782320900 + 419799121 = 27970^2 + 20489^2 .

It is an emirp because it is prime and its reverse (1200212021) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-1202120021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1202119984 and 1202120011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1202120027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 601060010 + 601060011.

It is an arithmetic number, because the mean of its divisors is an integer number (601060011).

Almost surely, 21202120021 is an apocalyptic number.

It is an amenable number.

1202120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1202120021 is an equidigital number, since it uses as much as digits as its factorization.

1202120021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1202120021 is about 34671.6025156035. The cubic root of 1202120021 is about 1063.2839950400.

Adding to 1202120021 its reverse (1200212021), we get a palindrome (2402332042).

The spelling of 1202120021 in words is "one billion, two hundred two million, one hundred twenty thousand, twenty-one".