91102210121 has 16 divisors (see below), whose sum is σ = 98882994000. Its totient is φ = 83433155328.

The previous prime is 91102210091. The next prime is 91102210139. The reversal of 91102210121 is 12101220119.

It can be written as a sum of positive squares in 8 ways, for example, as 238548025 + 90863662096 = 15445^2 + 301436^2 .

It is a cyclic number.

It is not a de Polignac number, because 91102210121 - 2¹⁰ = 91102209097 is a prime.

It is a super-2 number, since 2×91102210121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91102210093 and 91102210102.

It is not an unprimeable number, because it can be changed into a prime (91102210141) 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 in 15 ways as a sum of consecutive naturals, for example, 1671935 + ... + 1725563.

It is an arithmetic number, because the mean of its divisors is an integer number (6180187125).

Almost surely, 2^91102210121 is an apocalyptic number.

It is an amenable number.

91102210121 is a deficient number, since it is larger than the sum of its proper divisors (7780783879).

91102210121 is a wasteful number, since it uses less digits than its factorization.

91102210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54668.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 91102210121 in words is "ninety-one billion, one hundred two million, two hundred ten thousand, one hundred twenty-one".