20110109 has 2 divisors, whose sum is σ = 20110110. Its totient is φ = 20110108.

The previous prime is 20110087. The next prime is 20110141. The reversal of 20110109 is 90101102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19829209 + 280900 = 4453^2 + 530^2 .

It is a cyclic number.

It is not a de Polignac number, because 20110109 - 2¹² = 20106013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20110093 and 20110102.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20110169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055054 + 10055055.

It is an arithmetic number, because the mean of its divisors is an integer number (10055055).

Almost surely, 2^20110109 is an apocalyptic number.

It is an amenable number.

20110109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20110109 is an equidigital number, since it uses as much as digits as its factorization.

20110109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 20110109 is about 4484.4296181343. The cubic root of 20110109 is about 271.9389866393.

The spelling of 20110109 in words is "twenty million, one hundred ten thousand, one hundred nine".