100111121021 has 4 divisors (see below), whose sum is σ = 100111784700. Its totient is φ = 100110457344.

The previous prime is 100111120957. The next prime is 100111121027. The reversal of 100111121021 is 120121111001.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 78173364025 + 21937756996 = 279595^2 + 148114^2 .

It is a cyclic number.

It is not a de Polignac number, because 100111121021 - 2⁶ = 100111120957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 100111120993 and 100111121011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100111121027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15875 + ... + 447743.

It is an arithmetic number, because the mean of its divisors is an integer number (25027946175).

Almost surely, 2^100111121021 is an apocalyptic number.

It is an amenable number.

100111121021 is a deficient number, since it is larger than the sum of its proper divisors (663679).

100111121021 is an equidigital number, since it uses as much as digits as its factorization.

100111121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663678.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 100111121021 its reverse (120121111001), we get a palindrome (220232232022).

The spelling of 100111121021 in words is "one hundred billion, one hundred eleven million, one hundred twenty-one thousand, twenty-one".