205780157 has 16 divisors (see below), whose sum is σ = 228336192. Its totient is φ = 183889920.

The previous prime is 205780151. The next prime is 205780177. The reversal of 205780157 is 751087502.

It is a cyclic number.

It is not a de Polignac number, because 205780157 - 2¹⁸ = 205518013 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 (205780151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234203 + ... + 235079.

It is an arithmetic number, because the mean of its divisors is an integer number (14271012).

Almost surely, 2^205780157 is an apocalyptic number.

It is an amenable number.

205780157 is a deficient number, since it is larger than the sum of its proper divisors (22556035).

205780157 is a wasteful number, since it uses less digits than its factorization.

205780157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228.

The product of its (nonzero) digits is 19600, while the sum is 35.

The square root of 205780157 is about 14345.0394562023. The cubic root of 205780157 is about 590.3838897789.

The spelling of 205780157 in words is "two hundred five million, seven hundred eighty thousand, one hundred fifty-seven".