200120021009 has 4 divisors (see below), whose sum is σ = 203895870516. Its totient is φ = 196344171504.

The previous prime is 200120020987. The next prime is 200120021027. The reversal of 200120021009 is 900120021002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 900120021002 = 2 ⋅450060010501.

It can be written as a sum of positive squares in 2 ways, for example, as 148820035984 + 51299985025 = 385772^2 + 226495^2 .

It is a cyclic number.

It is not a de Polignac number, because 200120021009 - 2²⁸ = 199851585553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (200120021039) 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, 1887924674 + ... + 1887924779.

It is an arithmetic number, because the mean of its divisors is an integer number (50973967629).

Almost surely, 2^200120021009 is an apocalyptic number.

It is an amenable number.

200120021009 is a deficient number, since it is larger than the sum of its proper divisors (3775849507).

200120021009 is an equidigital number, since it uses as much as digits as its factorization.

200120021009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3775849506.

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

The spelling of 200120021009 in words is "two hundred billion, one hundred twenty million, twenty-one thousand, nine".