100123121 has 6 divisors (see below), whose sum is σ = 116469810. Its totient is φ = 85819776.

The previous prime is 100123097. The next prime is 100123123. The reversal of 100123121 is 121321001.

It can be written as a sum of positive squares in only one way, i.e., 73290721 + 26832400 = 8561^2 + 5180^2 .

It is not a de Polignac number, because 100123121 - 2⁶ = 100123057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100123123) 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 5 ways as a sum of consecutive naturals, for example, 1021616 + ... + 1021713.

It is an arithmetic number, because the mean of its divisors is an integer number (19411635).

Almost surely, 2^100123121 is an apocalyptic number.

It is an amenable number.

100123121 is a deficient number, since it is larger than the sum of its proper divisors (16346689).

100123121 is an equidigital number, since it uses as much as digits as its factorization.

100123121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2043343 (or 2043336 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 100123121 is about 10006.1541563180. The cubic root of 100123121 is about 464.3492975889.

Adding to 100123121 its reverse (121321001), we get a palindrome (221444122).

The spelling of 100123121 in words is "one hundred million, one hundred twenty-three thousand, one hundred twenty-one".