202120000009 has 4 divisors (see below), whose sum is σ = 204555180816. Its totient is φ = 199684819204.

The previous prime is 202119999989. The next prime is 202120000013. The reversal of 202120000009 is 900000021202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202120000009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202119999947 and 202120000001.

It is not an unprimeable number, because it can be changed into a prime (202120000109) 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, 1217590279 + ... + 1217590444.

It is an arithmetic number, because the mean of its divisors is an integer number (51138795204).

Almost surely, 2^202120000009 is an apocalyptic number.

It is an amenable number.

202120000009 is a deficient number, since it is larger than the sum of its proper divisors (2435180807).

202120000009 is an equidigital number, since it uses as much as digits as its factorization.

202120000009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2435180806.

The product of its (nonzero) digits is 72, while the sum is 16.

The spelling of 202120000009 in words is "two hundred two billion, one hundred twenty million, nine", and thus it is an aban number.