9842121217 has 16 divisors (see below), whose sum is σ = 10138966992. Its totient is φ = 9548154880.

The previous prime is 9842121193. The next prime is 9842121221. The reversal of 9842121217 is 7121212489.

It can be written as a sum of positive squares in 8 ways, for example, as 1618533361 + 8223587856 = 40231^2 + 90684^2 .

It is a cyclic number.

It is not a de Polignac number, because 9842121217 - 2²⁷ = 9707903489 is a prime.

It is a super-2 number, since 2×9842121217² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9842121017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7706583 + ... + 7707859.

It is an arithmetic number, because the mean of its divisors is an integer number (633685437).

Almost surely, 2^9842121217 is an apocalyptic number.

It is an amenable number.

9842121217 is a deficient number, since it is larger than the sum of its proper divisors (296845775).

9842121217 is a wasteful number, since it uses less digits than its factorization.

9842121217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2228.

The product of its digits is 16128, while the sum is 37.

The square root of 9842121217 is about 99207.4655305739. The cubic root of 9842121217 is about 2143.0365093099.

The spelling of 9842121217 in words is "nine billion, eight hundred forty-two million, one hundred twenty-one thousand, two hundred seventeen".