205171157 has 2 divisors, whose sum is σ = 205171158. Its totient is φ = 205171156.

The previous prime is 205171117. The next prime is 205171171. The reversal of 205171157 is 751171502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 162843121 + 42328036 = 12761^2 + 6506^2 .

It is a cyclic number.

It is not a de Polignac number, because 205171157 - 2¹⁸ = 204909013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205171117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102585578 + 102585579.

It is an arithmetic number, because the mean of its divisors is an integer number (102585579).

Almost surely, 2^205171157 is an apocalyptic number.

It is an amenable number.

205171157 is a deficient number, since it is larger than the sum of its proper divisors (1).

205171157 is an equidigital number, since it uses as much as digits as its factorization.

205171157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2450, while the sum is 29.

The square root of 205171157 is about 14323.7968779231. The cubic root of 205171157 is about 589.8009066823.

The spelling of 205171157 in words is "two hundred five million, one hundred seventy-one thousand, one hundred fifty-seven".