204687145 has 16 divisors (see below), whose sum is σ = 271671120. Its totient is φ = 147066624.

The previous prime is 204687139. The next prime is 204687167. The reversal of 204687145 is 541786402.

204687145 = 10116² + 10117².

It can be written as a sum of positive squares in 8 ways, for example, as 1225449 + 203461696 = 1107^2 + 14264^2 .

It is a cyclic number.

It is not a de Polignac number, because 204687145 - 2⁹ = 204686633 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is an unprimeable number.

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, 40150 + ... + 44959.

It is an arithmetic number, because the mean of its divisors is an integer number (16979445).

Almost surely, 2^204687145 is an apocalyptic number.

204687145 is the 10117-th centered square number.

It is an amenable number.

204687145 is a deficient number, since it is larger than the sum of its proper divisors (66983975).

204687145 is a wasteful number, since it uses less digits than its factorization.

204687145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85164.

The product of its (nonzero) digits is 53760, while the sum is 37.

The square root of 204687145 is about 14306.8915212215. The cubic root of 204687145 is about 589.3367486974.

The spelling of 204687145 in words is "two hundred four million, six hundred eighty-seven thousand, one hundred forty-five".