100109 has 2 divisors, whose sum is σ = 100110. Its totient is φ = 100108.

The previous prime is 100103. The next prime is 100129. The reversal of 100109 is 901001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64009 + 36100 = 253^2 + 190^2 .

It is a cyclic number.

It is not a de Polignac number, because 100109 - 2¹² = 96013 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 100109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50054 + 50055.

It is an arithmetic number, because the mean of its divisors is an integer number (50055).

2¹⁰⁰¹⁰⁹ is an apocalyptic number.

It is an amenable number.

100109 is a deficient number, since it is larger than the sum of its proper divisors (1).

100109 is an equidigital number, since it uses as much as digits as its factorization.

100109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9, while the sum is 11.

The square root of 100109 is about 316.4000632111. The cubic root of 100109 is about 46.4327466519.

The spelling of 100109 in words is "one hundred thousand, one hundred nine".