100120121 has 4 divisors (see below), whose sum is σ = 100198032. Its totient is φ = 100042212.

The previous prime is 100120091. The next prime is 100120159. The reversal of 100120121 is 121021001.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 121021001 = 1787 ⋅67723.

It is a cyclic number.

It is not a de Polignac number, because 100120121 - 2⁶ = 100120057 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 100120099 and 100120108.

It is not an unprimeable number, because it can be changed into a prime (100110121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36995 + ... + 39608.

It is an arithmetic number, because the mean of its divisors is an integer number (25049508).

Almost surely, 2^100120121 is an apocalyptic number.

It is an amenable number.

100120121 is a deficient number, since it is larger than the sum of its proper divisors (77911).

100120121 is an equidigital number, since it uses as much as digits as its factorization.

100120121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77910.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 100120121 is about 10006.0042474506. The cubic root of 100120121 is about 464.3446597597.

Adding to 100120121 its reverse (121021001), we get a palindrome (221141122).

The spelling of 100120121 in words is "one hundred million, one hundred twenty thousand, one hundred twenty-one".