204091615225 has 9 divisors (see below), whose sum is σ = 253076403853. Its totient is φ = 163271485120.

The previous prime is 204091615171. The next prime is 204091615241. The reversal of 204091615225 is 522516190402.

The square root of 204091615225 is 451765.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 122229249769 + 81862365456 = 349613^2 + 286116^2 .

It is a de Polignac number, because none of the positive numbers 2^k-204091615225 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2213649 + ... + 2304001.

Almost surely, 2^204091615225 is an apocalyptic number.

204091615225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

204091615225 is the 451765-th square number.

204091615225 is the 225883-rd centered octagonal number.

It is an amenable number.

204091615225 is a deficient number, since it is larger than the sum of its proper divisors (48984788628).

204091615225 is an frugal number, since it uses more digits than its factorization.

204091615225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180716 (or 90358 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The spelling of 204091615225 in words is "two hundred four billion, ninety-one million, six hundred fifteen thousand, two hundred twenty-five".