200121020009 has 2 divisors, whose sum is σ = 200121020010. Its totient is φ = 200121020008.

The previous prime is 200121019979. The next prime is 200121020023. The reversal of 200121020009 is 900020121002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194886931600 + 5234088409 = 441460^2 + 72347^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-200121020009 is a prime.

It is not a weakly prime, because it can be changed into another prime (200121020089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100060510004 + 100060510005.

It is an arithmetic number, because the mean of its divisors is an integer number (100060510005).

Almost surely, 2^200121020009 is an apocalyptic number.

It is an amenable number.

200121020009 is a deficient number, since it is larger than the sum of its proper divisors (1).

200121020009 is an equidigital number, since it uses as much as digits as its factorization.

200121020009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The spelling of 200121020009 in words is "two hundred billion, one hundred twenty-one million, twenty thousand, nine".