20001231109 has 2 divisors, whose sum is σ = 20001231110. Its totient is φ = 20001231108.

The previous prime is 20001231077. The next prime is 20001231179. The reversal of 20001231109 is 90113210002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16257015009 + 3744216100 = 127503^2 + 61190^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001231109 - 2⁵ = 20001231077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001231179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000615554 + 10000615555.

It is an arithmetic number, because the mean of its divisors is an integer number (10000615555).

Almost surely, 2^20001231109 is an apocalyptic number.

It is an amenable number.

20001231109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001231109 is an equidigital number, since it uses as much as digits as its factorization.

20001231109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 19.

The spelling of 20001231109 in words is "twenty billion, one million, two hundred thirty-one thousand, one hundred nine".