200121217973 has 2 divisors, whose sum is σ = 200121217974. Its totient is φ = 200121217972.

The previous prime is 200121217969. The next prime is 200121217981. The reversal of 200121217973 is 379712121002.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149856474769 + 50264743204 = 387113^2 + 224198^2 .

It is a cyclic number.

It is not a de Polignac number, because 200121217973 - 2² = 200121217969 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (200121217903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100060608986 + 100060608987.

It is an arithmetic number, because the mean of its divisors is an integer number (100060608987).

Almost surely, 2^200121217973 is an apocalyptic number.

It is an amenable number.

200121217973 is a deficient number, since it is larger than the sum of its proper divisors (1).

200121217973 is an equidigital number, since it uses as much as digits as its factorization.

200121217973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10584, while the sum is 35.

Adding to 200121217973 its reverse (379712121002), we get a palindrome (579833338975).

The spelling of 200121217973 in words is "two hundred billion, one hundred twenty-one million, two hundred seventeen thousand, nine hundred seventy-three".