2121020173 has 2 divisors, whose sum is σ = 2121020174. Its totient is φ = 2121020172.

The previous prime is 2121020137. The next prime is 2121020191. The reversal of 2121020173 is 3710201212.

Together with previous prime (2121020137) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1349680644 + 771339529 = 36738^2 + 27773^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121020173 - 2¹⁷ = 2120889101 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121020173.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121024173) 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, 1060510086 + 1060510087.

It is an arithmetic number, because the mean of its divisors is an integer number (1060510087).

Almost surely, 2^2121020173 is an apocalyptic number.

It is an amenable number.

2121020173 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121020173 is an equidigital number, since it uses as much as digits as its factorization.

2121020173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 2121020173 is about 46054.5347712904. The cubic root of 2121020173 is about 1284.8376854437.

Adding to 2121020173 its reverse (3710201212), we get a palindrome (5831221385).

The spelling of 2121020173 in words is "two billion, one hundred twenty-one million, twenty thousand, one hundred seventy-three".