20121202009 has 4 divisors (see below), whose sum is σ = 20168996260. Its totient is φ = 20073407760.

The previous prime is 20121202001. The next prime is 20121202039. The reversal of 20121202009 is 90020212102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4738257225 + 15382944784 = 68835^2 + 124028^2 .

It is a cyclic number.

It is not a de Polignac number, because 20121202009 - 2³ = 20121202001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20121202001) 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, 23896494 + ... + 23897335.

It is an arithmetic number, because the mean of its divisors is an integer number (5042249065).

Almost surely, 2^20121202009 is an apocalyptic number.

It is an amenable number.

20121202009 is a deficient number, since it is larger than the sum of its proper divisors (47794251).

20121202009 is an equidigital number, since it uses as much as digits as its factorization.

20121202009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47794250.

The product of its (nonzero) digits is 144, while the sum is 19.

It can be divided in two parts, 2012 and 1202009, that added together give a palindrome (1204021).

The spelling of 20121202009 in words is "twenty billion, one hundred twenty-one million, two hundred two thousand, nine".