202111009 has 8 divisors (see below), whose sum is σ = 204350472. Its totient is φ = 199879680.

The previous prime is 202111001. The next prime is 202111073. The reversal of 202111009 is 900111202.

It can be written as a sum of positive squares in 4 ways, for example, as 3385600 + 198725409 = 1840^2 + 14097^2 .

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 202111009 - 2³ = 202111001 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202110983 and 202111001.

It is not an unprimeable number, because it can be changed into a prime (202111001) 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, 57157 + ... + 60589.

It is an arithmetic number, because the mean of its divisors is an integer number (25543809).

Almost surely, 2^202111009 is an apocalyptic number.

It is an amenable number.

202111009 is a deficient number, since it is larger than the sum of its proper divisors (2239463).

202111009 is a wasteful number, since it uses less digits than its factorization.

202111009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4067.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 202111009 is about 14216.5751501548. The cubic root of 202111009 is about 586.8538932316.

The spelling of 202111009 in words is "two hundred two million, one hundred eleven thousand, nine".