201604909 has 4 divisors (see below), whose sum is σ = 219932640. Its totient is φ = 183277180.

The previous prime is 201604901. The next prime is 201604961. The reversal of 201604909 is 909406102.

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 not a de Polignac number, because 201604909 - 2³ = 201604901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201604901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9163849 + ... + 9163870.

It is an arithmetic number, because the mean of its divisors is an integer number (54983160).

Almost surely, 2^201604909 is an apocalyptic number.

It is an amenable number.

201604909 is a deficient number, since it is larger than the sum of its proper divisors (18327731).

201604909 is a wasteful number, since it uses less digits than its factorization.

201604909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18327730.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 201604909 is about 14198.7643476466. The cubic root of 201604909 is about 586.3636428311.

The spelling of 201604909 in words is "two hundred one million, six hundred four thousand, nine hundred nine".