204772509 has 16 divisors (see below), whose sum is σ = 313828800. Its totient is φ = 131807088.

The previous prime is 204772507. The next prime is 204772511. The reversal of 204772509 is 905277402.

It is an interprime number because it is at equal distance from previous prime (204772507) and next prime (204772511).

It is not a de Polignac number, because 204772509 - 2¹ = 204772507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204772501) 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 15 ways as a sum of consecutive naturals, for example, 129979 + ... + 131544.

It is an arithmetic number, because the mean of its divisors is an integer number (19614300).

Almost surely, 2^204772509 is an apocalyptic number.

204772509 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

204772509 is a deficient number, since it is larger than the sum of its proper divisors (109056291).

204772509 is a wasteful number, since it uses less digits than its factorization.

204772509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261561 (or 261555 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 204772509 is about 14309.8745277518. The cubic root of 204772509 is about 589.4186641986.

The spelling of 204772509 in words is "two hundred four million, seven hundred seventy-two thousand, five hundred nine".