20012100209 has 8 divisors (see below), whose sum is σ = 20706577320. Its totient is φ = 19317916800.

The previous prime is 20012100149. The next prime is 20012100211. The reversal of 20012100209 is 90200121002.

It can be written as a sum of positive squares in 4 ways, for example, as 5436850225 + 14575249984 = 73735^2 + 120728^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20012100209 - 2³² = 15717132913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20012100259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69989 + ... + 211949.

It is an arithmetic number, because the mean of its divisors is an integer number (2588322165).

Almost surely, 2^20012100209 is an apocalyptic number.

20012100209 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

20012100209 is a deficient number, since it is larger than the sum of its proper divisors (694477111).

20012100209 is a wasteful number, since it uses less digits than its factorization.

20012100209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146851.

The product of its (nonzero) digits is 72, while the sum is 17.

The spelling of 20012100209 in words is "twenty billion, twelve million, one hundred thousand, two hundred nine".