200121001 has 2 divisors, whose sum is σ = 200121002. Its totient is φ = 200121000.

The previous prime is 200120993. The next prime is 200121007. The reversal of 200121001 is 100121002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154355776 + 45765225 = 12424^2 + 6765^2 .

It is a cyclic number.

It is not a de Polignac number, because 200121001 - 2³ = 200120993 is a prime.

It is not a weakly prime, because it can be changed into another prime (200121007) 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, 100060500 + 100060501.

It is an arithmetic number, because the mean of its divisors is an integer number (100060501).

Almost surely, 2^200121001 is an apocalyptic number.

It is an amenable number.

200121001 is a deficient number, since it is larger than the sum of its proper divisors (1).

200121001 is an equidigital number, since it uses as much as digits as its factorization.

200121001 is an odious number, because the sum of its binary digits is odd.

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

The square root of 200121001 is about 14146.4130082505. The cubic root of 200121001 is about 584.9214602233.

Adding to 200121001 its reverse (100121002), we get a palindrome (300242003).

Subtracting from 200121001 its reverse (100121002), we obtain a palindrome (99999999).

The spelling of 200121001 in words is "two hundred million, one hundred twenty-one thousand, one".